Arsenic Contamination of Environment

 Phosphorous

Kerl et al. (2018) believe that phosphorus is considered a key element for plant growth, but its impact is seen to be of different types on arsenic influence in the uptake of rice. The author further states that the outcome of phosphate on the sorption/desorption of arsenic in the soil environment is mainly used as a form of crop fertiliser because of its effect. However, Iqbal et al. (2019) cite that the bioavailable fraction of arsenic in soils to crop plants depends on the soil's various physical and chemical properties. It is important that these properties are considered before it can be assessed if the extraction of arsenic can be carried out easily or not. Xu et al. (2019) further criticise the notion by citing that large additions to phosphate are relevant to high anion-fixing soils or even alkaline pH or Fe and AI oxide that could impact the solubility of arsenic. At the same time, it should be noted that arsenic sensitivity is linked with phosphate nutrition in plants.  Once the intracellular phosphate levels are increased, it would help make the rice seedling resistant to the effects of arsenic. This is an area that many developing countries need to focus on.

 Microorganisms

Panthri and Gupta (2019) state that microorganisms tend to have a diverse impact on the arsenic that influences the uptake in rice.  The author mentions in his study that the idea was to analyse the impact of using various microorganisms on the uptake in rice. It was revealed that two types of bacteria species worked towards protecting the rice plants when they were under attack. The root target for the microbes was that they would reside in the rhizosphere, which is the soil around the plant robes. According to Mondal et al. (2019), the idea of having microorganisms defending the plant from the rice blast fungus worked in favour of the rice as it helped prevent any kind of adverse reaction on the rice. However, Kalita et al. (2018) believe that more than protecting the plant, it was important to mobilise the iron plaque that tends to accumulate at the base of plants which is the area where arsenic is present in. The microbe, EA106, is considered to be extremely effective in this aspect as it effectively prevents the poison from reaching the plants and making it useless from being used.

 Organic Matter

Kwon, Nejad and Jung (2017) mention in their study that organic matter tends to have diverse impacts on the arsenic in the soils, affecting rice uptake. The idea here is to analyse how organic matter tends to decrease the arsenic, irrespective of the source from which the organic matter has come. The author believes that farmyard manure was the main source in his study that helped him analyse the decrease of arsenic in the soil. However, Cui et al. (2019) cite that apart from farmyard manure, vermicompost was also an organic matter that significantly influenced decreasing arsenic. At this point, the author further cites that the treatment used to decrease arsenic was not a vital factor because he had not used the treatment on some arsenic soils in some areas of his experiment. He had just applied the vermicompost, which worked its way through cutting the arsenic in the soil and decreased the satisfaction of the element significantly. It can be considered one of the ways to prevent the rise of arsenic in rice plants.

 Flooding

Flooding occurs in the rice plants' soil due to climate change, which is considered a major hindrance to plant growth and performance, as per Gustave et al. (2019). The author further mentions in his study that any form of increased atmospheric carbon dioxide and temperature would adversely impact plant growth and performance. If there is an increased atmospheric carbon dioxide, it will stimulate the photosynthetic rate of rice, which would also increase the water and nutrient use of the photosynthetic product. This eventually causes the biomass to increase, along with yields. However, Afzal, Hussain and Farooqi (2018) believe that flooding is focused on inducing the reductive dissolution of iron oxyhydroxide minerals and reducing the arsenic adsorbed on soil minerals. This increases the dissolved concentrations and the availability of arsenic as well. Therefore, it is important to understand that there need to be preventive measures to ensure that flooding is prevented from taking place (Gharachorloo et al., 2019; Bakhat et al., 2019). Zhang et al. (2020) cite that draining the water is not an option that can be considered here as this would deprive the plant of numerous essential nutrients vital for its growth and development.

 Discussion

Challenges in the food chain due to the presence of arsenic

The study's primary objective is to identify the challenges associated with the food chain due to the presence of arsenic. The studies of Afzal, Hussain and Farooqi (2018); Bakhat et al. (2017) indicated that the major challenge in a food chain is the presence of arsenic in drinking water, which creates a threat to all the living thing that consumes the drinking water. Similarly, the research of Thakur, Gupta and Chattopadhyay (2013); Singh (2015); Nachman et al. (2018) in content analysis indicated that arsenic-contaminated drinking water is one of the major challenges of arsenic in the food chain as it affects the health of entities consuming contaminated water with arsenic toxicity. Health threats such as cancer and respiratory diseases are commonly caused by arsenic toxicity (Ghosh et al. 2012). Additionally, the research of Awasthi et al. (2017) in literature contemplated that inorganic composites of arsenic are sodium arsenite, arsenic trioxide, arsenic acid and arsenates, arsenic trichloride, and arsenic pentoxide, which are lead and calcium arsenates that impose a serious threat on the health of humans.

The studies of Kumarathilaka et al. (2018) from literature considered food as a major determinant of arsenic toxicity among humans. A similar author added that contaminated food had been used in irrigation and agriculture of highly consumed food by humans and animals, which consequently creates a challenge in the food chain due to increased toxicity. Similarly, the research of Dahlawi et al. 2018; Kabay et al. (2019) from content stated that arsenic found in groundwater had been utilised in the irrigation of crops that makes multiple fruits, vegetables and cereals toxic due to which the health of entire food chain is exposed to a risk of severe long-term diseases. Furthermore, the studies of Majumdar, Kumar and Bose (2020) from literature regarded that the primary challenge caused by arsenic is contaminating the groundwater, which is a primary source of water consumption in multiple nations. Thus, it exposes those individuals to arsenic toxicity and affects the food chain. Whereas the studies of Ghosh et al. (2012); Molin et al. (2015) in content analysis highlighted that drinking water is used for irrigating soil and growing crops that, consequently, affects humans' health when consumed as a food.

The role of arsenic in the contamination of soil

Arsenic is considered the element that naturally causes soil contamination, used in both inorganic and organic forms. Additionally, significant inorganic arsenic composites are used in many agricultural processes, such as arsenic trioxide, arsenic pentoxide, sodium arsenite, etc. (Awasthi et al., 2017). Furthermore, fish's organoarsenicals, which comprise dimethloxyarsylethanol, arsenocholine, and trimethylarsonium lactate, contaminate the water and affect the sealife; however; the impact of methylarsonic and dimethylarsinic acids is low (Afzal, Hussain and Farooqi, 2018).

Similarly, it has been evaluated in the research findings that the excessive accumulation of Arsenic in the soil cause empty panicle in rice and a straighthead disease in crops (Srivastava et al., 2013). Further, the consumption in low amounts affects the plants by exposure to Arsenic through soil contamination from biochemical or morphological changes (Srivastava et al., 2015). The role of Arsenic in poisoning groundwater has harmful consequences. The elevated levels of Arsenic contaminate the soil through industrial processes, and tobacco plants are the main causes of Arsenic exposure to groundwater (Abbas et al., 2018). Moreover, the study also analysed that the countries such as China, Bangladesh, Mexico, India, etc., have huge contaminated lands due to natural and man-made processes (WHO, 2020). Further, it has been investigated that the volcanic activities, the mineral weathering, mining and smelting processes cause the ingression of Arsenic into the soil and contaminate it through its carcinogenic characteristics.

Arsenic also impacts the soil by using fertilizers, pesticides and wood preservatives which have huge amounts of lead arsenate. The areas near such industries suffer from deadly diseases that can be due to breathing near contaminated soil (Abbas et al., 2018). However, some processes are developed to reduce the impact of arsenic in affecting the soil, such as physical excavation, extraction techniques, chemical oxidation, soil solidification, R&D methods, etc. (Srivastava et al., 2013).

Impact of arsenic on the food chain

The impact of various factors of bioavailability/soil concentrations plays the main role in the uptake of rice. The main impacts that would be analysed are from the point of the effect of manganese and iron, the influence of pH, the effect of phosphate, microorganisms, organic substances, and flooding. Bakhat et al. (2017) state in their study that manganese and iron precipitate as iron and manganese oxides in a toxic atmosphere. The author further states that there is a rising similarity between iron and manganese oxides and arsenic, along with residue redox possible. The firmness of iron and iron (hydr)oxides mainly depends on the pH of the deposit. Azam, Sarker and Naz (2016) state that the pH of the soil contributes to the activity of flexibility and bioavailability of arsenic. The author further states that arsenic has elevated similarity for oxide surfaces. Kwon, Nejad and Jung (2017) believe that under aerobic environments, arsenic V is known to be the key type of arsenic in soils and views with the nutrient phosphorous of the plant in the form of phosphate (PV). Zecchin et al. (2017) assert that research shows that arbuscular mycorrhizal fungi (AMF) can upsurge arsenic lenience in plants. Wang et al. (2020) believe that organic material is a complicated matter of practical organic acids, which is attained from the decay of water and terrestrial plants and animals. Costa et al. (2016) mention that flooding is the main factor in arsenic uptake in rice plants. The author further states that extensive repetition of rice farming comprises endless flooding in the irrigated land.

In contrast to the above findings, various authors have stated that each of the factors tends to have a different impact on the role of arsenic in the influence of uptake in rice. For instance, Cui et al. (2019) cite that apart from farmyard manure, vermicompost was also an organic matter that significantly influenced decreasing arsenic. At this point, the author further cites that the treatment used to decrease arsenic was not a vital factor because he had not used the treatment on some arsenic soils in some areas of his experiment. In relation to the pH, Srivastava, Suprasanna and Tripathi (2020) state that adjusting pH through the use of a pH meter of 0.1 N sulfuric acid or 0.1 N sodium hydroxide solutions. The experiment was then carried out through five variables: pH of the solution, adsorbent dosage, contact time, initial concentration of arsenic and temperature. The result was that there was an increase in the removal efficiency of arsenic. It cannot be said with certainty how efficient the removal was, but it has been reported that it has been made possible to a certain extent.

Factors related to arsenic that influence the uptake in rice

Bakhat et al. (2019) are of the view that combined evidence proves that high rice product nations, which are India, Bangladesh, Taiwan, and China, tend to exceed the usual absorption of arsenic in soil (10.0 mg/kg) and the extreme standard allowed by the United States Environmental Protection Agency which is 20.0mg/kg. In China and Taiwan, the organic arsenic composite roxarsone exists in poultry brood which is usually utilised as a fertiliser for rice that is at sea-level rice, which the plants immerse. Chatterjee, Sharma and Gupta (2017) believe that rice grain yield is decreased by arsenic absorption of the soil where the limit of the roxarsone/kg soil which killed rice plant was 200mg. It can be seen clearly that the arsenic absorption in the rice grain surpassed the statutory acceptable limit that has been set by the WHO (Wang et al., 2020).

Basu et al. (2015) believe that if arsenic usage is controlled within the food chain, it will not cause as much harm to the ecosystem as it is known for. There are diverse kinds of safe drinking-water techniques that can be implemented to ensure that the arsenic content is decreased. Mitigation techniques or looking for alternative sources of water can be considered to help countries with a high presence of arsenic in their water (Kumar et al., 2015). Mitra et al. (2017) state that the major source through which arsenic enters the food chain is water. Therefore, there is a major need to ensure that the arsenic content is reduced in water in some ways.

It can be observed from the above findings that although arsenic is an element that cannot be extracted completely from the water system, certain measures can be taken to ensure that arsenic element is controlled in the rice plants, which would prevent any further damage to the food chain. The idea here is that developing countries need to take appropriate measures to ensure that they are working towards finding a solution to help them with this specific cause.

 Summary

In this chapter, the findings and discussion have been carried out in relation to the aim and objective of the study. It has been revealed through the findings that the presence of arsenic in the food chain is a vital element that cannot be completely eradicated; however, some measures can be taken to ensure that it is controlled and the impact of it is as less as possible on the food chain. From the discussion, it has been analysed that although arsenic cannot be removed, there is a need for developing countries to ensure that they are taking measures to implement various ways to mitigate the presence of the arsenic element. This would help them to ensure that any adverse impact of arsenic on the food chain is as minimal as possible, as well as has a minimum negative impact on the entire ecosystem comprising animals, plants and human lives.

CONCLUSION AND RECOMMENDATIONS

Introduction

Arsenic is a toxic material for humans, animals and plants, and its harsh consequences are increasing because of its use in large amounts in soil and food. Some anthropogenic activities and mining release it into the soil and through irrigation, where contaminated water is used (Li et al., 2014). The increased uptake of arsenic in rice and its adverse health effects made the topic of research significant. Therefore, to contribute to the research, this study was carried out to identify the factors that influence the uptake of arsenic in rice. The research was conducted to explore the challenges on the food chain due to Arsenic, to assess the role of arsenic in soil contamination, to analyse the impact of arsenic in the food chain and identify the factors related to arsenic that influence the uptake in rice. This research has been conducted through content analysis and a systematic review of the previously published studies.

This chapter of the research has assessed the summary of the findings by analysing each objective. Further, the chapter presented recommendations in order to reduce the Arsenic in the food chain that influences the uptake of rice. Lastly, it explained the future implications of the research and the conclusion for the topic of the study.

Summarised Findings

The research has analysed the challenges of arsenic associated with the food chain. It was identified that the major challenge is the presence of Arsenic in the drinking water, which is a threat to human lives as the hazardous material causes harmful diseases. Additionally, it was also investigated in the research findings that the toxic Arsenic compounds affect human life by affecting the crops and animals; this is a crucial challenge in the food chain. Similarly, arsenic is found in abundance in groundwater. It is excessively used in the irrigation of crops, which makes the fruits and vegetables toxic, and this exposure is a risk of causing severe and long-term diseases to humans, being a challenge for the food chain. Another primary challenge that arose from Arsenic was determined in the residents of West Bengal, India and Bangladesh as they drink water from the wells. Also, the threat to the food chain is due to the growing use of rice, which increases skin, lung and bladder diseases.

The second research objective was to examine Arsenic's role in soil contamination and has identified that Arsenic, in combination with organic and inorganic materials, contaminate the soil. Further, Arsenic contaminates the soil in the form of many harmful combinations, such as the organoarsenicals comprising dimethloxyarsylethanol, arsenocholine, and trimethylarsonium lactate affecting water through the sea. In contrast, inorganic composites of arsenic are sodium arsenite, arsenic trioxide, arsenic acid and arsenates, arsenic trichloride, and arsenic pentoxide, which contaminate the soil and affects the lives of human. Further, Arsenic contaminates the groundwater, and through soil contamination, the level of contaminants is also increased due to the exposure of Arsenic to natural resources. Industries also produce Arsenic and greatly affect soil contamination by using it to develop metal adhesives, pigments, paper, glass, etc. It has also been explored in the research findings that Arsenic causes soil contamination from the anthropogenic activities, processing ore, farming or tanning hides, weathering of minerals and some natural processes such as volcanic activity.

The impact of arsenic on the food chain was analysed in the research findings. It was identified that the ecosystem is affected by the presence of arsenic in the food chains. If the usage of arsenic is reduced, there will be control over a number of harmful consequences of arsenic consumption. The vital aspect affecting arsenic availability in food chains includes the organic carbon content, ionic robustness of the soil solution, pH, cation conversation capacity and iron oxides. Another factor that influences arsenic uptake in rice is the bioavailability of arsenic present in the soil.

Further, many short-term and long-term techniques can be used as safety measures for the high use of arsenic faced by many countries in the world, especially in the food chain industry. Additionally, the government can take action against the excessive use of arsenic in multiple industries; they can integrate it by collaborating with communities and introducing solid knowledge about arsenic. The partnerships with all sectors associated with agricultural, water and public health sectors can also take some efficient measures for reducing the effects of arsenic in the food chain.

The last objective of the research was to assess the factors related to arsenic that influence the uptake in rice. The main factors determined from the research findings are the influence of pH, the effect of manganese and iron, the effect of phosphate, organic substances, microorganisms and flooding. It was investigated that the iron and manganese oxides are toxic to the atmosphere and are similar to arsenic. Iron and manganese decrease the flexibility of arsenic in the deep soil horizons, which leads to the growing arsenic in topsoil. Moreover, the pH of the soil actively participates in the bioavailability of arsenic and has elevated similarity on the oxide surfaces. Low pH is responsible for the arsenic's low extractability compared to other elements such as zinc and cadmium.

Furthermore, the arsenic V and PV allocate the comparable transport pathway in rice roots which are the key types of arsenic in soils with the nutrient phosphorus. Arbuscular mycorrhizal fungi (AMF), a microorganism, are known to reduce the rice grains' organic and inorganic proportion gain. It was evaluated that flooding is also a main factor in arsenic uptake in rice plants due to the excessive repetition of rice farming in irrigated land.

Recommendations

By examining the analysis, it has been found that major challenges of arsenic in the food chain include contaminated drinking water and arsenic toxicity in irrigation and agriculture due to unhealthy groundwater. It has also been found that multiple food substances such as rice, maize and wheat are affected with arsenic toxicity during growth and irrigation, which seriously threaten human health. In light of the above analysis, it is recommended that training on discriminating high-arsenic and low-arsenic sources must be given to farmers to that the contaminated food and drinking water do not reach the final consumer in the food chain. Furthermore, actions like blending low-arsenic water with high-arsenic water to get to acceptable concentration level of arsenic must be taken to minimise the threat to the food chain. Lastly, an arsenic removal system must be installed at multiple places so that the arsenic toxicity can be minimised to a possible extent that does not impose a higher risk on the health of people

• The first recommendation is to provide training to farmers and multiple professionals involved in irrigation and agriculture for discriminating high-arsenic and low-arsenic sources at places with high arsenic toxicity. Thus, it would reduce the level of arsenic- toxicity in rice and promote the uptake of rising among the population.
• The second recommendation is to initiate the practice of blending low-arsenic water with high-arsenic water in order to get to an acceptable concentration level of arsenic that could reduce the level of arsenic in rice and facilitate the citizens in uptaking of rice.
• The final recommendation is to install the arsenic removal system at multiple places, such as agricultural sites and industrial areas, so that arsenic-free food growth and production take place and minimise the threat of affecting people's health, promoting the uptaking of rice.

Future Implication

The current study aimed to identify the role of arsenic in affecting the food chain. The study would be primarily helpful for multiple governments, as it recommends multiple ways to control the damage of arsenic on food substances. Additionally, the current research would assist the people working in the agricultural sector to take necessary steps for minimising arsenic toxicity in irrigation and growing crops. Furthermore, the current study would facilitate rice consumers, highlighting the process by which the soil gets affected by arsenic toxicity and suggesting measures for reducing soil contamination so that the consumers can uptake the rice. In addition, the current study would encourage multiple health regularities for installing an arsenic removal system at places with a high risk of consuming food that is affected by arsenic toxicity. Similarly, the current study would promote various governments for providing training to farmers and multiple professionals involved in irrigation and agriculture for discriminating high-arsenic and low-arsenic sources at places with high arsenic toxicity.

Moreover, the current research would help initiate the practice of blending low-arsenic water with high-arsenic water in order to get to an acceptable concentration level of arsenic that could possibly reduce the level of arsenic in a nation like Bangladesh, India and West Bengal, where the rice is extensively consumed, and groundwater have a high toxicity level of arsenic. The current research can also be used by future researchers interested in studying the similar phenomena and want to contribute to increasing the literature related to arsenic contamination. Additionally, the current study would assist WHO and other health regularities in increasing awareness of potential damage caused by arsenic like chemical substances and the risk it would create to people's health.

Conclusion

The current study aimed to identify the role of arsenic in the food chain and the factors influencing the rise. Additionally, the current research highlighted the challenges in the food chain due to the presence of arsenic. Furthermore, the study analysed the role of arsenic in the contamination of soil, followed by the impact of arsenic in the food chain and identified the factors related to arsenic that influence the uptake in rice. The current study considered Nightingale’s Environmental Theory and The Theory of Pollution Policy to conceptualise arsenic's environmental effect in multiple nations. In addition, the study highlighted the factors related to arsenic that influence the uptake of rice, which was identified as groundwater irrigation. As the nature of the current study is highly critical, the study employed a content analysis technique for analysing the authentic data from secondary sources such as journals, articles, and books.

After examining the data, the study found that irrigation and agriculture are major areas with a prominent risk of arsenic toxicity in the food chain. Additionally, the consumption of contaminated drinking water is also evaluated as a primary source that raises a challenge on the food chain due to the high concentration of arsenic. Furthermore, the study identified that contaminated water used on soil is a major source of contaminating soil that affects the health of humans by touching, digging and eating the soil, which increases the chance of causing harmful skin, liver and respiratory diseases among humans. Similarly, the study also found that the factors that influence arsenic accumulated in rice grains are plant physiology, method of processing rice and type of rice cultivar. Lastly, the study evaluated that brown rice accounted more for arsenic toxicity than white rice. After analysing the findings, the study presented brief recommendations which were training on discriminating high-arsenic and low-arsenic sources that must be provided to farmers who can prevent the contaminated food and water from reaching the final consumer. Moreover, another recommendation was to promote the practice of blending low-arsenic water with high-arsenic water in order to get an acceptable concentration level of arsenic. At the same time, the final recommendation was to install the arsenic removal system at necessary places to minimise the risk of arsenic toxicity on human health.

REFERENCES

Abbas, G., Murtaza, B., Bibi, I., Shahid, M., Niazi, N.K., Khan, M.I., Amjad, M. and Hussain, M., 2018. Arsenic uptake, toxicity, detoxification, and speciation in plants: physiological, biochemical, and molecular aspects. International journal of environmental research and public health, 15(1), p.59.

Abdul, K.S.M., Jayasinghe, S.S., Chandana, E.P., Jayasumana, C. and De Silva, P.M.C., 2015. Arsenic and human health effects: A review. Environmental toxicology and pharmacology, 40(3), pp.828-846.

Afzal, B., Hussain, I. and Farooqi, A., 2018. Arsenic in Paddy Soils and Potential Health Risk. In Environmental Pollution of Paddy Soils (pp. 151-163). Springer, Cham.

Althobiti, R.A., Sadiq, N.W. and Beauchemin, D., 2018. Realistic risk assessment of arsenic in rice. Food chemistry, 257, pp.230-236.

Antwi, S.K. and Hamza, K., 2015. Qualitative and quantitative research paradigms in business research: A philosophical reflection. European journal of business and management, 7(3), pp.217-225.

Armat, M.R., Assarroudi, A., Rad, M., Sharifi, H. and Heydari, A., 2018. Inductive and deductive: Ambiguous labels in qualitative content analysis. The Qualitative Report, 23(1), pp.219-221.

Ashraf, U., Kanu, A.S., Mo, Z., Hussain, S., Anjum, S.A., Khan, I., Abbas, R.N. and Tang, X., 2015. Lead toxicity in rice: effects, mechanisms, and mitigation strategies—a mini review. Environmental Science and Pollution Research, 22(23), pp.18318-18332.

Åström, S.T.E.F.A.N., 2017. On the robustness of air pollution policy cost-benefit analysis. Department of.

Awasthi, S., Chauhan, R., Srivastava, S., and Tripathi, R. D., 2017. The journey of arsenic from soil to grain in rice. Frontiers in plant science, 8, pp.1007.

Azam, S.M.G.G., Sarker, T.C. and Naz, S., 2016. Factors affecting the soil arsenic bioavailability, accumulation in rice and risk to human health: a review. Toxicology mechanisms and methods, 26(8), pp.565-579.

Bakhat, H.F., Zia, Z., Abbas, S., Hammad, H.M., Shah, G.M., Khalid, S., Shahid, N., Sajjad, M. and Fahad, S., 2019. Factors controlling arsenic contamination and potential remediation measures in soil-plant systems. Groundwater for Sustainable Development, p.100263.

Bastías, J. M., and Beldarrain, T., 2016. Arsenic translocation in rice cultivation and its implication for human health. Chilean journal of agricultural research, 76(1), pp.114-122.

Basu, B., Kundu, M., Hedayatullah, M., Kundu, C.K., Bandyopadhyay, P., Bhattacharya, K. and Sarkar, S., 2015. Mitigation of arsenic in rice through deficit irrigation in field and use of filtered water in kitchen. International Journal of Environmental Science and Technology, 12(6), pp.2065-2070.

Carlin, D.J., Naujokas, M.F., Bradham, K.D., Cowden, J., Heacock, M., Henry, H.F., Lee, J.S., Thomas, D.J., Thompson, C., Tokar, E.J. and Waalkes, M.P., 2016. Arsenic and environmental health: state of the science and future research opportunities. Environmental health perspectives, 124(7), pp.890-899.

Cui, M.Q., Wu, C., Jiang, X.X., Liu, Z.Y. and Xue, S.G., 2019. Bibliometric analysis of research on soil arsenic during 2005–2016. Journal of Central South University, 26(2), pp.479-488.

Dahlawi, S., Naeem, A., Iqbal, M., Farooq, M.A., Bibi, S. and Rengel, Z., 2018. Opportunities and challenges in the use of mineral nutrition for minimizing arsenic toxicity and accumulation in rice: a critical review. Chemosphere, 194, pp.171-188.

Davis, M.A., Signes-Pastor, A.J., Argos, M., Slaughter, F., Pendergrast, C., Punshon, T., Gossai, A., Ahsan, H. and Karagas, M.R., 2017. Assessment of human dietary exposure to arsenic through rice. Science of the Total Environment, 586, pp.1237-1244.

de Florence Nightingale, T.A. and Crítica, U.A., 2015. The Florence Nightingale’s environmental theory: a critical analysis. Escola Anna Nery Revista de Enfermagem, 19, p.3.

de Vries, F.P. and Hanley, N., 2016. Incentive-based policy design for pollution control and biodiversity conservation: a review. Environmental and Resource Economics, 63(4), pp.687-702.

DHSS. 2020. ARSENIC CONTAMINATED SOIL. [Online] Available at: <https://dhss.delaware.gov/dph/files/arsenicsoilfaq.pdf> [Accessed 14 April 2020].

Ebenstein, A., Fan, M., Greenstone, M., He, G. and Zhou, M., 2017. New evidence on the impact of sustained exposure to air pollution on life expectancy from China’s Huai River Policy. Proceedings of the National Academy of Sciences, 114(39), pp.10384-10389.

Erlingsson, C. and Brysiewicz, P., 2017. A hands-on guide to doing content analysis. African Journal of Emergency Medicine, 7(3), pp.93-99.

Gharachorloo, M., Zulfiqar, A., Bayat, M.H. and Bahrami, F., 2019. Arsenic Tracking in Iranian Rice: Analysis of Agricultural Soil and Water, Unpolished Rice and White Rice. Journal of Food Biosciences and Technology, 9(1), pp.19-34.

Ghosh, A., Awal, M.A., Majumder, S., Sikder, M.H. and Rao, D.R., 2012. Arsenic residues in broiler meat and excreta at arsenic prone areas of Bangladesh. Bangladesh Journal of Pharmacology, 7(3), pp.178-185.

Gustave, W., Yuan, Z.F., Ren, Y.X., Sekar, R., Zhang, J. and Chen, Z., 2019. Arsenic alleviation in rice by using paddy soil microbial fuel cells. Plant and Soil, 441(1-2), pp.111-127.

Hennink, M., Hutter, I. and Bailey, A., 2020. Qualitative research methods. SAGE Publications Limited.

Hojsak, I., Braegger, C., Bronsky, J., Campoy, C., Colomb, V., Decsi, T., Domellöf, M., Fewtrell, M., Mis, N.F., Mihatsch, W. and Molgaard, C., 2015. Arsenic in rice: a cause for concern. Journal of pediatric gastroenterology and nutrition, 60(1), pp.142-145.

Hu, B. and McKitrick, R., 2016. Decomposing the environmental effects of trade liberalization: The case of consumption-generated pollution. Environmental and Resource Economics, 64(2), pp.205-223.

Iqbal, M., Rahman, G.M., Panaullah, G.M., Kabir, H. and Biswas, J.C., 2019. Influence of Soil Arsenic Levels on Biomass Production and Relationship the Concentration of Arsenic between Rice Straw and Grain. Asian Journal of Soil Science and Plant Nutrition, pp.1-10.

Jain, N. and Chandramani, S., 2018. Arsenic poisoning-An overview. Indian Journal of Medical Specialities, 9(3), pp.143-145.

Jason, L. and Glenwick, D. eds., 2016. Handbook of methodological approaches to community-based research: Qualitative, quantitative, and mixed methods. Oxford university press.

Johnston, M.P., 2017. Secondary data analysis: A method of which the time has come. Qualitative and quantitative methods in libraries, 3(3), pp.619-626.

Kabay, N., Bundschuh, J., Hendry, B., Bryjak, M., Yoshizuka, K., Bhattacharya, P. and Anac, S. eds., 2010. The global arsenic problem: challenges for safe water production. CRC Press.

Kalita, J., Pradhan, A.K., Shandilya, Z.M. and Tanti, B., 2018. Arsenic stress responses and tolerance in rice: physiological, cellular and molecular approaches. Rice Science, 25(5), pp.235-249.

Kamau, S.M., 2015. Applying Florence Nightingale’s Model of Nursing and the Environment on Multiple Drug Resistant Tuberculosis Infected Patients in the Kenyan Setting. Open Access Library Journal, 2(08), p.1.

Kerl, C.F., Rafferty, C., Clemens, S. and Planer-Friedrich, B., 2018. Monothioarsenate uptake, transformation, and translocation in rice plants. Environmental science & technology, 52(16), pp.9154-9161.

Kumar, S., Dubey, R.S., Tripathi, R.D., Chakrabarty, D. and Trivedi, P.K., 2015. Omics and biotechnology of arsenic stress and detoxification in plants: current updates and prospective. Environment international, 74, pp.221-230.

Kwon, J.C., Nejad, Z.D. and Jung, M.C., 2017. Arsenic and heavy metals in paddy soil and polished rice contaminated by mining activities in Korea. Catena, 148, pp.92-100.

Li, J., Dong, F., Lu, Y., Yan, Q., and Shim, H., 2014. Mechanisms controlling arsenic uptake in rice grown in mining impacted regions in South China. PloS one, 9(9).

Li, Y., Ye, F., Wang, A., Wang, D., Yang, B., Zheng, Q., Sun, G. and Gao, X., 2016. Chronic arsenic poisoning probably caused by arsenic-based pesticides: findings from an investigation study of a household. International journal of environmental research and public health, 13(1), p.133.

Lin, Z., Wang, X., Wu, X., Liu, D., Yin, Y., Zhang, Y., Xiao, S. and Xing, B., 2018. Nitrate reduced arsenic redox transformation and transfer in flooded paddy soil-rice system. Environmental Pollution, 243, pp.1015-1025.

Lindsay, E.R. and Maathuis, F.J., 2017. New molecular mechanisms to reduce arsenic in crops. Trends in plant science, 22(12), pp.1016-1026.

Ma, L., Wang, L., Jia, Y. and Yang, Z., 2016. Arsenic speciation in locally grown rice grains from Hunan Province, China: spatial distribution and potential health risk. Science of the Total Environment, 557, pp.438-444.

Mack, L., 2010. The philosophical underpinnings of educational research.

Masuda, H., 2018. Arsenic cycling in the Earth’s crust and hydrosphere: interaction between naturally occurring arsenic and human activities. Progress in Earth and Planetary Science, 5(1).

Mishra, S., Mattusch, J. and Wennrich, R., 2017. Accumulation and transformation of inorganic and organic arsenic in rice and role of thiol-complexation to restrict their translocation to shoot. Scientific reports, 7(1), pp.1-13.

Mitra, A., Chatterjee, S., Moogouei, R. and Gupta, D.K., 2017. Arsenic accumulation in rice and probable mitigation approaches: a review. Agronomy, 7(4), p.67.

Mohai, P. and Saha, R., 2015. Which came first, people or pollution? A review of theory and evidence from longitudinal environmental justice studies. Environmental Research Letters, 10(12), p.125011.

Molin, M., Ulven, S.M., Meltzer, H.M. and Alexander, J., 2015. Arsenic in the human food chain, biotransformation and toxicology–Review focusing on seafood arsenic. Journal of trace elements in Medicine and Biology, 31, pp.249-259.

Mondal, D., Mwale, T., Xu, L., Matthews, H., Oyeka, A., Lace-Costigan, G. and Polya, D.A., 2019. Risk perception of arsenic exposure from rice intake in a UK population. Palgrave Communications, 5(1), pp.1-7.

Mughal, F.B. and Irshad Ali, B.H., 2017. Enhancing patient well-being: Applying environmental theory in nursing practice. Annals of Nursing and Practice, 4(3), p.1085.

Nachman, K.E., Punshon, T., Rardin, L., Signes-Pastor, A.J., Murray, C.J., Jackson, B.P., Guerinot, M.L., Burke, T.A., Chen, C.Y., Ahsan, H. and Argos, M., 2018. Opportunities and challenges for dietary arsenic intervention. Environmental health perspectives, 126(8), p.084503.

Otero, X.L., Tierra, W., Atiaga, O., Guanoluisa, D., Nunes, L.M., Ferreira, T.O. and Ruales, J., 2016. Arsenic in rice agrosystems (water, soil and rice plants) in Guayas and Los Ríos provinces, Ecuador. Science of the Total Environment, 573, pp.778-787.

Pandey, D., Zoomi, I., Akhtar, O., Srivastava, P. and Kehri, H.K., 2018. Approaches for Remediation of Arsenic Contamination from Soil and Water: A Review. Int J Life Sci Res, 6, pp.146-162.

Panthri, M. and Gupta, M., 2019. Plausible strategies to reduce arsenic accumulation in rice. In Advances in Rice Research for Abiotic Stress Tolerance (pp. 371-384). Woodhead Publishing.

Pathak, V., Jena, B. and Kalra, S., 2013. Qualitative research. Perspectives in clinical research, 4(3).

Pham, L.T.M., 2018. A Review of Key Paradigms: Positivism. Interpretivism & Critical Inquiry, School of Education, The University of Adelaide.

Pirani, S., 2016. Application of Nightingale’s theory in nursing practice. Annals of Nursing and Practice, 3(1), p.1040.

Pope III, C.A., Cropper, M., Coggins, J. and Cohen, A., 2015. Health benefits of air pollution abatement policy: Role of the shape of the concentration–response function. Journal of the Air & Waste Management Association, 65(5), pp.516-522.

Rahman, M.A., Rahman, A., Khan, M.Z.K. and Renzaho, A.M., 2018. Human health risks and socio-economic perspectives of arsenic exposure in Bangladesh: a scoping review. Ecotoxicology and environmental safety, 150, pp.335-343.

Rowe, E.C., Ford, A.E., Smart, S.M., Henrys, P.A. and Ashmore, M.R., 2016. Using qualitative and quantitative methods to choose a habitat quality metric for air pollution policy evaluation. PloS one, 11(8).

Ruíz-Huerta, E.A., de la Garza Varela, A., Gómez-Bernal, J.M., Castillo, F., Avalos-Borja, M., SenGupta, B. and Martínez-Villegas, N., 2017. Arsenic contamination in irrigation water, agricultural soil and maize crop from an abandoned smelter site in Matehuala, Mexico. Journal of hazardous materials, 339, pp.330-339.

Schmidt, C.W., 2015. In search of “just right”: the challenge of regulating arsenic in rice.

Seyfferth, A.L., Morris, A.H., Gill, R., Kearns, K.A., Mann, J.N., Paukett, M. and Leskanic, C., 2016. Soil incorporation of silica-rich rice husk decreases inorganic arsenic in rice grain. Journal of agricultural and food chemistry, 64(19), pp.3760-3766.

Shakoor, M.B., Niazi, N.K., Bibi, I., Murtaza, G., Kunhikrishnan, A., Seshadri, B., Shahid, M., Ali, S., Bolan, N.S., Ok, Y.S. and Abid, M., 2016. Remediation of arsenic-contaminated water using agricultural wastes as biosorbents. Critical Reviews in Environmental Science and Technology, 46(5), pp.467-499.

Shi, T., Liu, H., Chen, Y., Wang, J. and Wu, G., 2016. Estimation of arsenic in agricultural soils using hyperspectral vegetation indices of rice. Journal of hazardous materials, 308, pp.243-252.

Shri, M., Singh, P.K., Kidwai, M., Gautam, N., Dubey, S., Verma, G. and Chakrabarty, D., 2019. Recent advances in arsenic metabolism in plants: current status, challenges and highlighted biotechnological intervention to reduce grain arsenic in rice. Metallomics, 11(3), pp.519-532.

Shrivastava, A., Barla, A., Singh, S., Mandraha, S. and Bose, S., 2017. Arsenic contamination in agricultural soils of Bengal deltaic region of West Bengal and its higher assimilation in monsoon rice. Journal of hazardous materials, 324, pp.526-534.

Silverman, D. ed., 2016. Qualitative research. Sage.

Singh, S.K., 2015. Groundwater arsenic contamination in the Middle-Gangetic Plain, Bihar (India): the danger arrived. International Research Journal of Environment Sciences, 4(2), pp.70-76.

Singh, S.K., 2015. Groundwater arsenic contamination in the Middle-Gangetic Plain, Bihar (India): the danger arrived. International Research Journal of Environment Sciences, 4(2), pp.70-76.

Smith, A., 2018. Integrated Pollution Control: change and continuity in the UK industrial pollution policy network. Routledge.

Soiferman, L.K., 2010. Compare and Contrast Inductive and Deductive Research Approaches. Online Submission.

Srivastava, P.K., Singh, M., Singh, N. and Tripathi, R.D., 2013. Soil arsenic pollution: a threat to crops. Journal of Bioremediation & Biodegradation, 4(7).

Srivastava, S., Suprasanna, P. and Tripathi, R.D., 2020. Safeguarding Rice from Arsenic Contamination Through the Adoption of Chemo-agronomic Measures. In Arsenic in Drinking Water and Food (pp. 411-424). Springer, Singapore.

Srivastava, S., Upadhyay, M.K., Tripathi, R.D. and Dhankher, O.P., 2016. Arsenic transport, metabolism and toxicity in plants. Int. J. Plant Environ, 2, pp.1-2.

Suriyagoda, L.D., Dittert, K. and Lambers, H., 2018. Mechanism of arsenic uptake, translocation and plant resistance to accumulate arsenic in rice grains. Agriculture, Ecosystems & Environment, 253, pp.23-37.

Tchounwou, P., Yedjou, C., Patlolla, A. and Sutton, D., 2012. Heavy Metal Toxicity and the Environment. Experientia Supplementum, pp.133-164.

Thakur, B.K., Gupta, V. and Chattopadhyay, U., 2013. Arsenic groundwater contamination related socio-economic problems in India: Issues and challenges. In Knowledge systems of societies for adaptation and mitigation of impacts of climate change (pp. 163-182). Springer, Berlin, Heidelberg.

Trinh, Q.D., 2018, April. Understanding the impact and challenges of secondary data analysis. In Urologic Oncology: Seminars and Original Investigations (Vol. 36, No. 4, pp. 163-164). Elsevier.

Vaismoradi, M., Jones, J., Turunen, H. and Snelgrove, S., 2016. Theme development in qualitative content analysis and thematic analysis.

Wang, H.Y., Wen, S.L., Chen, P., Zhang, L., Cen, K. and Sun, G.X., 2016. Mitigation of cadmium and arsenic in rice grain by applying different silicon fertilizers in contaminated fields. Environmental Science and Pollution Research, 23(4), pp.3781-3788.

Wang, X., Peng, B., Tan, C., Ma, L. and Rathinasabapathi, B., 2015. Recent advances in arsenic bioavailability, transport, and speciation in rice. Environmental Science and Pollution Research, 22(8), pp.5742-5750.

WHO. 2018. Arsenic. [Online] Available at: <https://www.who.int/news-room/fact-sheets/detail/arsenic> [Accessed 14 April 2020].

Xu, B., Yu, J., Zhong, Y., Guo, Y., Ding, J., Chen, Y. and Wang, G., 2019. Influence of Br24 and Gr24 on the accumulation and uptake of Cd and As by rice seedlings grown in nutrient solution. regulation of plant growth and development, 19, p.20.

Zalaghi, H. and Khazaei, M., 2016. The role of deductive and inductive reasoning in accounting research and standard setting. Asian Journal of Finance & Accounting, 8(1), pp.23-37.

Zecchin, S., Corsini, A., Martin, M. and Cavalca, L., 2017. Influence of water management on the active root-associated microbiota involved in arsenic, iron, and sulfur cycles in rice paddies. Applied microbiology and biotechnology, 101(17), pp.6725-6738.

Zhang, S., Geng, L., Fan, L., Zhang, M., Zhao, Q., Xue, P. and Liu, W., 2020. Spraying silicon to decrease inorganic arsenic accumulation in rice grain from arsenic-contaminated paddy soil. Science of The Total Environment, 704, p.135239.

Zhao, F.J. and Wang, P., 2020. Arsenic and cadmium accumulation in rice and mitigation strategies. Plant and Soil, 446(1), pp.1-21.

Zia, Z., Bakhat, H.F., Saqib, Z.A., Shah, G.M., Fahad, S., Ashraf, M.R., Hammad, H.M., Naseem, W. and Shahid, M., 2017. Effect of water management and silicon on germination, growth, phosphorus and arsenic uptake in rice. Ecotoxicology and environmental safety, 144, pp.11-18. s