A survey of arsenic in foodstuffs on sale in the United Kingdom and imported from Bangladesh

Science of the Total Environment 337 (2005) 23 – 30 www.elsevier.com/locate/scitotenv

A survey of arsenic in foodstuffs on sale in the United Kingdom and imported from Bangladesh S.W. Al Rmallia, P.I. Harisa,*, C.F. Harringtonb, M. Ayuba a b

Leicester School of Pharmacy, Faculty of Health and Life Sciences, De Montfort University, Leicester, LE1 9BH, UK Cancer Biomarkers and Prevention Group, Leicester University, Biocentre, University Road, Leicester, LE1 7RH, UK Received 23 February 2004; received in revised form 11 June 2004; accepted 12 June 2004

Abstract Arsenic is a highly toxic element and its presence in food composites is a matter of concern to the well being of both humans and animals. Arsenic-contaminated groundwater is often used in Bangladesh and West Bengal (India) to irrigate crops used for food and animal consumption, which could potentially lead to arsenic entering the human food chain. In this study, we used graphite furnace atomic absorption spectroscopy to determine the total arsenic concentrations in a range of foodstuffs, including vegetables, rice and fish, imported into the United Kingdom from Bangladesh. The mean and range of the total arsenic concentration in all the vegetables imported from Bangladesh were 54.5 and 5–540 Ag/kg, respectively. The highest arsenic values found were for the skin of Arum tuber, 540 Ag/kg, followed by Arum Stem, 168 Ag/kg, and Amaranthus, 160 Ag/ kg. Among the other samples, freshwater fish contained total arsenic levels between 97 and 1318 Ag/kg. The arsenic content of the vegetables from the UK was approximately 2- to 3-fold lower than those observed for the vegetables imported from Bangladesh. The levels of arsenic found in vegetables imported from Bangladesh in this study, in some cases, are similar to those previously recorded for vegetables grown in arsenic-affected areas of West Bengal, India, although lower than the levels reported in studies from Bangladesh. While the total arsenic content detected in our study in vegetables, imported from Bangladesh, is far less than the recommended maximum permitted level of arsenic, it does provide an additional source of arsenic in the diet. This raises the possibility that the level of arsenic intake by certain sectors of the UK population may be significantly higher then the general population and requires further investigations. D 2004 Elsevier B.V. All rights reserved. Keywords: Graphite furnace atomic absorption spectroscopy; Arsenic; Food; Bangladesh; Diet

1. Introduction * Corresponding author. Tel.: +44 116 2506306; fax: +44 116 257 7135. E-mail addresses: [email protected] (P.I. Haris)8 [email protected] (M. Ayub). 0048-9697/$ - see front matter D 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.scitotenv.2004.06.008

The accumulation of trace elements in environmental samples (soil, sediment, water, biota, etc.) can cause a potential risk to human health due to the

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transfer of these elements in aquatic media, their uptake by plants and subsequent introduction into the food chain. It is therefore necessary to monitor human exposure to toxic trace elements present in the food chain, and a number of studies have reported the total arsenic content of foodstuffs from different countries (Dabeka et al., 1993; Tsuda et al., 1995; Sapunar-Postruznik et al., 1996; Roychowdhury et al., 2002, 2003; Meharg and Mazibur, 2003; Alam et al., 2003; Das et al., 2004). Arsenic is ubiquitous in the environment, being naturally present in soil, air, water and food, and concentrations may be increased by anthropogenic contamination (Villa-Lojo et al., 2002). It is present in the environment in a number of different inorganic and organic chemical forms due to its participation in complex biological and chemical processes. Some of the most important arsenic species from a toxicological perspective include the two oxidation states As (III), As (V), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), arsenobetaine and arsenocholine. Humans are exposed to many different inorganic and organic arsenic species present in food, water and other environmental media. Routes of arsenic intake include respiratory for dust and fumes and oral for water, beverages, soil and food. The most common mode of arsenic toxicity in humans is the inactivation of an enzyme system by binding through various biological ligands (Nagvi et al., 1994). Humans who are occupationally exposed, such as in the industrial application of wood treatments, are routinely monitored for arsenic exposure by bodies such as the Health and Safety Executive (UK). Chronic exposure to inorganic arsenic may give rise to several health effects on the gastrointestinal tract, respiratory tract, skin, liver, cardiovascular system, hematopoietic system, nervous system, etc. Some of these human health effects are currently being observed in populations in south and southeastern Asia, particularly in countries such as Bangladesh, India and Taiwan. Arsenic is recognized as a toxic element and has been classified as a human carcinogen to skin and lungs (WHO, 1980). It has been reported that the toxicity of arsenic decreases with increasing methylation (Londesborough et al., 1999), although, recently, it has been reported that trivalent forms of MMA and DMA can be more carcinogenic than inorganic As (Vega et al., 2001).

Bangladesh, a country in South Asia with a population of about 150 million, is one of a number of countries that has arsenic contamination in its groundwater, which results from the underlying mineralogy and geology of the area. Arsenic contamination has been reported in groundwater in 41 out of the 64 districts in Bangladesh (Samanta et al., 1999). About 61% of the water analysed from tube wells has arsenic content above 0.05 mg/l and about 13% have arsenic content above 0.01 mg/l (Ali and Tarafdar, 2003). The average concentration of arsenic in contaminated water is about 0.26 mg/l with a maximum level of 0.83 mg/l. This is significantly higher than the World Health Organization (WHO) maximum permissible limit in drinking water which is 0.05 mg/l and the recommended value is 0.01 mg/l (WHO, 2001). The Environment Protection Agency (EPA) has recently adjusted the upper limit for arsenic in drinking water to 0.01 mg/l (EPA, 2001). Groundwater is the main source of potable water in Bangladesh and the agricultural system is mostly groundwater-dependent. Food chain aspects of arsenic contamination in Bangladesh have recently received attention (Duxbury et al., 2003; Meharg and Mazibur, 2003). Arsenic contamination in the Bangladeshi staple food, rice, showed presence of high levels of arsenic 1700 Ag/kg (Meharg and Mazibur, 2003). Relatively high concentration of arsenic has also been recently detected in vegetables grown in the arsenic-affected region of Bangladesh (Alam et al., 2003; Das et al., 2004). The Bangladeshi population in the United Kingdom is quite significant and they consume large quantities of food imported from Bangladesh. Our objective in this study was to analyse certain imported foodstuffs for their total arsenic content using graphite furnace atomic absorption spectroscopy (GFAAS) to determine whether this section of the UK population is being exposed to high concentrations of arsenic in their diet. Similar studies have been conducted to estimate the level of arsenic in foods in a number of other countries. For example, in Croatia (Sapunar-Postruznik et al., 1996), low levels of arsenic were recorded in fruits (0.2 Ag/kg) and vegetables (0.4 Ag/kg). Foods were collected from different cities in Canada between 1985 and 1988 and the mean and range of arsenic concentrations in all samples reported were 73.2 and b0.1– 4830 Ag/kg, respectively (Dabeka et al., 1993). In Japan, over a 2-year period, a total diet study (market

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basket survey) was conducted and used to estimate the concentration of arsenic in the diet, results showing intake levels between 160 and 280 Ag per day (Tsuda et al., 1995). In the USA, the daily total arsenic intake was estimated to be 88 Ag per day (Gunderson, 1991) and, in the United Kingdom, was estimated to be 65 Ag per day (Ministry of Agriculture, Fisheries and Food, 2000). The arsenic concentrations in the seafood samples were quite high: 2360 Ag/kg of total arsenic in saltwater fish compared to 74 Ag/kg of inorganic arsenic for rice (Schoof et al., 1999). In a recent study conducted in West Bengal, India, an area known to have high levels of arsenic in the groundwater, the levels of arsenic in vegetables were in the range of b0.04–690 Ag/kg (Roychowdhury et al., 2002) and in rice, b0.04–605 Ag/kg (Roychowdhury et al., 2003). However, the mean and range of arsenic in vegetables grown in an arsenic-affected region of Bangladesh were 225 and 19–489 Ag/kg, respectively (Alam et al., 2003), and the range of arsenic in vegetables was 70– 3990 Ag/kg (Das et al., 2004). In our study, we determine the total arsenic concentration in some foodstuffs on sale in the UK, but imported from Bangladesh. For comparison purposes, produce grown in the UK and other EU countries was also analysed for their arsenic content.

2. Methodology 2.1. Sampling and sample preparation Samples were collected from markets in Leicester City, UK, during the months of September 2002 and January 2003. The foodstuffs were identified as fully as possible (Table 1), thoroughly washed with doubledistilled water (DDW) and then cut and separated into different parts where applicable (leaf, stalks and roots). These were then dried in an oven (Gallenkamp, Hotbox oven) overnight at 80 8C until constant weight. The samples were homogenized by grinding and stored in a desiccator in the dark until analysis, usually within the same week. The dried sample (0.5–1.0 g) was digested in 10 ml of ultrapure 14N nitric acid (Romil-UpA, Ultra Purity acid) and 2 ml of H2O2 (30%, AnalaR, DBH, England) by reflux digestion (120 8C for 2 h) using a standard published method (Gallagher et al., 2001).

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Table 1 Some of the foodstuffs sampled and their local, English and scientific names where possible Local name (Bangla)

English namea

Kochu Mukhi Kochu Kochu Loti Pan Lau

Arum (Colocasia–Araceae) Arum tuber (Colocasia–Araceae) Arum shoot (Colocasia–Araceae) Betel leaf Squash/bottle gourd (Lagenaria Siceraria–Cucurbitaceae) Amaranthus (Amaranthus lividus) Lime (type of Citrus fruit) Kantola Shrimp (Puntius gonionotus)

Data Sak Shatkora Kakrol Chingri Puti a

Where possible, the scientific name is given inside the parentheses.

The solutions were filtered through ash-free paper and adjusted to 50 ml with DDW. 2.2. Instrumentation The atomic absorption spectrometer (Varian model 220-Z) was used in conjunction with a graphite-furnace atomizer (GTA-110) equipped with Zeeman background correction. Arsenic was determined at the 193.7-nm wavelength, using a 1000F3 mg/l standard solution of arsenic (CPI International, USA) diluted to 65 Ag/l with 1% nitric acid. The calibration standards in the range 0–25.33 Ag/l were prepared on line via the automix facility on the autosampler. Palladium 1000 mg/l was used as the matrix modifier. The instrumental parameters used for the GFAAS analysis are those supplied in the software by the instrumental manufacture. 2.3. Method validation and analytical figures of merit The detection limit for arsenic was evaluated by the analysis of 10 replicate determinations of the reagent blank (limit of detection=3standard deviation of the concentration of 10 replicate determinations) and determined to be 0.25 Ag/l. The analytical procedure was validated by analysis of a certified reference material (Seaweed CRM 9, NIES, Japan) containing a total concentration of arsenic of 115F9 mg/kg. The measured amount of arsenic in three replicate digests was 119F12 mg/kg, which corresponds to a recovery of 104%.

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The analytical results of total arsenic concentration from all foodstuff samples are summarized in Tables 2 and 3 below. All levels of arsenic are reported as micrograms of total arsenic per kilogram. The average value was achieved using two replicate measurements of the same sample taking into account the correction by the recovery value. In addition, the range and the standard deviation (S.D.) were determined.

A reagent blank and the CRM were analysed with each batch of samples. The calibration curve was fitted over the concentration range between 3.62 and 25.33 Ag/l with r=0.9991.

3. Results and discussion A total of 20 different foodstuff samples were collected from markets in Leicester in the United Kingdom, which were imported from Bangladesh, in order to determine their arsenic content. For comparison purposes, 11 vegetable samples, sold in the local markets that were of European origin, were also purchased for determining their arsenic content.

3.1. Comparison of arsenic content of Bangladeshi foodstuffs sold in the UK with those grown in arsenicaffected region of Bangladesh and India The concentration of arsenic in vegetables from Bangladesh ranged from 5 to 540 Ag/kg, with a mean of 54.5 Ag/kg (40.5 without arum tuber skin).

Table 2 Arsenic contents (Ag/kg) in food composites imported from Bangladesh and purchased from Leicester City in the United Kingdom Common name

Bengali name

n

Mean

Std. dev.

Range

Vegetables Arum leaf Arum stem Arum shoot Arum tuber (skin) Arum tuber (flesh) Amaranthus Squash Aubergine Kantola Shatkora lime (Citrus Fruit) Potato Radish Beans Chili All vegetable categories

Kochu Patha Kochu Data Kochu Loti Mukhi Kochu Mukhi Kochu Data Sak Lau Begoon Kakrol Shatkora Aloo Moola Sim Morich

4 8 10 10 8 8 4 2 2 2 2 2 2 2 68

65.6 89.4 40.9 257 30.7 74.4 37.1 b5 41.7 39.1 27.4 30.0 37.1 b5 54.5 (40.5)*

5.3 55.9 10.3 159 37.1 80.2 14.2 – – – – – – – 60.9

59.8–72.4 39.1–168 21.9–60.9 33.1–540 b5–76.5 15.2–160 23.1–52.1 b5 38.6–44.8 37.6–40.6 26.1–28.6 27.9–31.9 34.7–39.6 b5 b5–540

Fish Shrimp King prawn Bombay duck Puti All fish categories

Chingri Goldha Chingri Loitka Puti

2 4 2 6 14

264 113 223 580 350

– 19 – 498 375

262–266 97–140 214–231 245–1318 97–1318

Other foods Rice raw Betel leaf Honey Date syrup molasses Lemon Olive All other categories

Chal Pan Modhu Khejurer Ghur Lebu Jholfoi

4 2 2 2 2 2 14

*

Mean without Arum tuber skin is 40.5.

11.3 45.9 18.2 9 b5 b5 15.1

7.6 – – – – – 13.7

b5–20.2 44.9–46.9 16.8–19.6 7.9–10.1 b5 b5 b5–46.9

S.W. Al Rmalli et al. / Science of the Total Environment 337 (2005) 23–30 Table 3 Arsenic contents (Ag/kg) in vegetables of European origin, purchased in Leicester City market Name

n

Mean

Range

Carrots Radish Potatoes Parsnips Beetroot Marrow Leek Spring onion Aubergine Broccoli Cabbage All samples

4 2 2 2 2 2 2 2 2 2 2 24

10.1 15.7 9.2 7.4 b5 78.2 11 17 27.6 14.7 60.8 24.2

9.8–10.4 14.9–16.5 9.1–9.3 6.7–8.1 b5 69.5–87 10.9–11.1 13.6–20.3 27.6–27.7 14–15.4 53–68.5 b5–87

However, the concentration of arsenic in fish ranged from 97 to 1318 Ag/kg, with a mean value of 350 Ag/ kg. As far as the freshwater fish are concerned, Puti (Puntius gonionotus) has a very high arsenic concentration of 1318 Ag/kg with a mean of 580 Ag/kg. A dried form of this fish, popular in certain parts of Bangladesh, was used in this study. The arsenic content in this fish is an order of magnitude greater than freshwater king prawn (113 Ag/kg), freshwater shrimp (264 Ag/kg) and a seawater fish popularly known as Bombay duck (223 Ag/kg). However, it is likely that the majority of this is present as nontoxic arsenobetaine. The speciation of arsenic was not the subject of this study, but it has been widely reported that arsenic in fish is present as nontoxic arsenobetaine. Arsenobetaine has been reported to constitute about 70% of total arsenic in all fish tissue samples (Ebisuda et al., 2002). The arum plant has been reported to contain high levels of arsenic, but the literature reports have been rather vague as it was not clear where in the plant this high level of arsenic is located. Therefore, we have investigated the arsenic content of this plant in its various parts in great detail. Of all the different vegetables investigated, the skin isolated from the tuber of the arum tuber contained the highest mean arsenic concentrations (257 Ag/kg with a maximum value of 540 Ag/kg). In contrast, the flesh of the arum tuber (after peeling off the skin) and arum stem contains only 76.5 and 89.4 Ag/kg of arsenic, respectively. The content of arsenic in the leaf (59.8–72.4 Ag/kg) and (Stem 39.1–168 Ag/kg) of the arum plant was also

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determined. Our survey of the arsenic content in different parts of the arum plant reveals that the highest level of arsenic detected is localised in the skin of its tuber which is not consumed by human beings. The higher level of arsenic in the arum tuber could be explained by the fact that it is found under the ground in contact with potentially arsenic-contaminated soil. Other vegetables showing a significant amount of arsenic is the Amaranthus plant (15.2–160 Ag/kg) and potato (26.1–28.6 Ag/kg). In recent surveys of arsenic content of foodstuff in Bangladesh (Alam et al., 2003; Das et al., 2004), various vegetables were sampled from regions of Bangladesh that are known to have high levels of arsenic in the groundwater. According to Alam et al., the highest levels of arsenic were detected in ghotkol, taro (loti from arum plant) and snake gourd with values of 446, 440 and 489 Ag/kg, respectively. The mean was found to be 225 Ag/kg for all vegetables. Compared to this, the mean arsenic content in vegetable investigated in our study is lower. However, arsenic content for some specific vegetables is similar. For example, the arsenic content for potato and taro are similar to those found by Alam et al. (2003). It is interesting that a significantly higher level of arsenic was found for the skin of arum tuber compared to the value quoted by Alam et al. (2003). However, it is not clear if their result was for the skin, flesh or both. In a more recent study by Das et al. (2004), the leaf of this plant was found to contain between 90 and 3990 Ag/kg of arsenic. In contrast, in our study, the value was 59.8–72.4 Ag/kg. Das et al. (2004) also reported high levels of arsenic in potatoes (70–1360 Ag/kg). This is much higher than detected in our study (26.1–28.6 Ag/kg). The study by Alam et al. (2003) and Das et al. (2004) focused on vegetables specifically selected from regions of Bangladesh that are known to contain very high levels of arsenic in groundwater. In our case, we do not know if those vegetables used in our study, which were imported into the UK, came from an arsenic-affected region of Bangladesh. Nevertheless, the particularly high levels of arsenic detected in these vegetables, compared to similar vegetables grown in the UK/EU (see below), do suggest that they may still originate from arsenic-affected regions, albeit from a less affected region than the ones investigated by Alam et al. (2003) and Das et al. (2004). This is highly plausible considering the scale of the problem in Bangladesh,

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where 41 out of the 64 districts are known to contain high levels of arsenic in their groundwater (Samanta et al., 1999). Our study focused on a small group of samples over a period of a few months and does not provide a full picture of the range of arsenic concentration that may be found in vegetables imported into the UK. There is always the possibility that, after a comprehensive survey, arsenic values as high as 3990 Ag/kg (as detected by Das et al., 2004), exceeding food safety limits, may be detected in vegetables imported into the UK from Bangladesh. In a recent study, Roychowdhury et al. (2002) surveyed arsenic content in food collected in Jalangi and Domkal blocks from the arsenicaffected area of West Bengal, India. The food categories containing the mean arsenic concentrations were vegetables (92 and 123 Ag/kg), cereals and bakery goods (156 and 294 Ag/kg), spices (92 and 207 Ag/kg) and others, which include fish (138 and 137 Ag/kg) for Jalangi and Domkal blocks, respectively. High concentration of arsenic was found in arum leaf (331 and 341 Ag/kg), rice (226 and 245 Ag/kg) and fish (830 Ag/kg). Compared with the West Bengal study, the mean arsenic concentrations in vegetables (from Bangladesh) in our study are slightly lower. The groundwater is often the main source of drinking water and agricultural irrigation in Bangladesh and West Bengal. The highest concentration of arsenic in our

survey of foodstuff from Bangladesh was found in dried Puti fish, a freshwater fish (1318 Ag/kg). Compared with fish from the arsenic-affected region of West Bengal, the arsenic concentration in Puti from Bangladesh was higher. The skin of most root vegetables (although this is usually not eaten by humans) is likely to contain the highest amount of arsenic, as it is most likely to be in direct contact with arsenic-contaminated soil. As pointed out earlier, in our study, the highest value of arsenic was found in the tuber of the arum plant (540 Ag/ kg), although after peeling off the skin, the arsenic concentration decreases in the fleshy part (76.5 Ag/ kg). The arsenic content of foodstuff from the arsenic-affected region (Jalangi and Domkal) of West Bengal (Roychowdhury et al., 2003) showed a mean level of 20.9 and 21.2 Ag/kg in vegetables. Compared with these results, the mean of arsenic in our study for vegetables from Bangladesh is 2-fold higher. 3.2. Comparison of arsenic content of Bangladeshi vegetables sold in the UK with those grown in the UK and other parts of the world The total arsenic concentrations of some selected vegetables (Table 3) grown in the UK/EU showed the mean and range of arsenic concentrations to be 24.2 and 5–87 Ag/kg. The highest arsenic concentrations

Table 4 Comparison of the results from our study with those published by others Foodstuff from

Arsenic concentrations (Ag/kg) Mean

Bangladesh (vegetables)a Bangladesh (rice only)a Bangladesha,b West Bengal, Indiaa West Bengal, Indiaa Japan (total diet) Bangladesh (our study) UK/EU (our study) Canada UK (Food Standards Agency) Croatia a b c d

496 225 123 81.1 54.5 (40.5) c 24.2 7 2 (4.9)d 0.4

Reference Range 70–3990 58–1830 19–489 b0.04–690 b0.04–605 160–280 b5–540 b5–87 b 0.1–84.0 b0.5–7.4 0–1.5

The foodstuff analysed in these studies were collected from known arsenic-affected regions. These values were estimated from the bar charts presented by Alam et al. (2003). The mean without Arum tuber skin is 40.5. Food Standards Agency mean for green vegetables (2) and other vegetables (4.9).

Das et al., 2004 Meharg and Mazibur, 2003 Alam et al., 2003 Roychowdhury et al., 2002 Roychowdhury et al., 2003 Tsuda et al., 1995 DMU (UK) DMU (UK) Dabeka et al., 1993 FSA, 2003 Sapunar-Postruznik et al., 1996

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were 87.2 Ag/kg for marrow and 68.5 Ag/kg for cabbage. When comparing the results from Tables 2 and 3, UK/EU vegetables versus imported from Bangladesh vegetables, the mean arsenic concentrations are approximately 2- to 3-fold higher for the latter. For example, potatoes show the arsenic concentration to be approximately 3-fold higher and radish is approximately 2-fold higher. Table 4 shows levels of arsenic reported in the literature for foodstuff from Croatia (Sapunar-Postruznik et al., 1996), Japan (Tsuda et al., 1995), Canada (Dabeka et al., 1993) and the United Kingdom (Food Standards Agency, 2003). Food collected in Canadian cities (Dabeka et al., 1993) in the years 1985–1988 was analysed for total arsenic, and the food groups containing the mean arsenic concentrations were fish (1662 Ag/kg), meat and poultry (24.3 Ag/kg), vegetables (7 Ag/kg) and fruit and fruit juices (4.5 Ag/kg). Compared with the Canadian study, the mean arsenic concentrations in vegetables (from Bangladesh) in our study are approximately 6- to 8-fold higher. Clearly, the mean arsenic concentration in vegetables in our study is significantly higher compared to countries that are not known to be affected by high levels of arsenic in the environment, for example, Canada, UK and some EU countries. However, the levels of arsenic concentrations found in our study are similar to results obtained by others for arsenic-affected regions of West Bengal (India) and Bangladesh. The results of this study show that vegetables imported from Bangladesh contain between 2- and over 100-fold higher concentrations of arsenic compared with vegetables grown in UK, EU, North America and Croatia. Furthermore, the levels of arsenic content in vegetables imported into the UK from Bangladesh are, to some extent, similar to values previously reported for vegetables grown in arsenicaffected regions of West Bengal and Bangladesh. This suggests that vegetables imported into the UK from Bangladesh may originate from arsenic-affected areas. It is important to point out that in our study, the nature of the arsenic species (inorganic and organic arsenic compounds) present in the food samples was not determined, although this is necessary from a toxicological point of view. Studies are in progress in our laboratory to obtain information in this area. However, a previous Canadian study reported that more than 60% of the total arsenic in foodstuffs

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exists in the more harmful inorganic form (Dabeka et al., 1993). According to WHO (1981), 1.0 mg of inorganic arsenic per day may give rise to skin lesions within a few years. The provisional maximum tolerable daily intake (PMTDI) of inorganic arsenic in the UK is 120 Ag. It has been estimated from a UK government total diet study that the daily intake of arsenic from the average diet in the UK is about 65 Ag total arsenic per day for the general population and about 17 Ag for vegetarians (Ministry of Agriculture, Fisheries and Food, 2000). Unfortunately, there are no data available regarding the average daily intake of arsenic by the Bangladeshi community residing in the UK, who are the main consumers of vegetables and foodstuff imported from Bangladesh. It is likely that their daily intake of arsenic may be significantly higher than the value of 65 Ag reported for the general UK population. It is therefore important to carry out a detailed study on the dietary arsenic intake by this sector of the UK population and ascertain if it constitutes any serious effect on their health. This is particularly important as the content of arsenic found in our study is, in some cases, similar to levels found in arsenicaffected regions of Bangladesh and India. The implication of our study is that a section of the UK population may be unknowingly consuming arsenic-contaminated food. This could have serious long-term health problems for these people that need to be explored in detail.

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