Remediation in Food

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Remediation in Food Domingo A. Román-Silva

CONTENTS 9.1 Introduction................................................................................................... 187 9.2 Arsenic Contamination in Chicken, Swine, Goat, and Cattle....................... 188 9.3 Arsenic Contamination in Rice, Cereals, Fruits, and Other Vegetable Products........................................................................................ 189 9.4 Arsenic-Enriched Environments................................................................... 190 9.5 Agricultural Environments............................................................................ 190 9.6 Mining-Related Environments...................................................................... 191 9.7 Riverine and Volcanic Environments............................................................ 191 9.8 Arsenic Contamination in Beer and Wine.................................................... 194 9.9 Arsenic Contamination in Juice Fruits and Soft Drinks............................... 196 9.10 Arsenic Contamination in Herbal Medicines and Spices.............................. 197 9.11 Remediation/Mitigation of Arsenic Toxicity Impacts................................... 199 9.12 Mitigation/Remediation Strategies................................................................200 9.13 Mitigation of As Consumption through Food...............................................202 9.14 Agricultural Practices....................................................................................202 9.15 Regulatory Need for Arsenic Mitigation.......................................................205 9.16 Preventive Treatments for Human Beings Exposed to Arsenic....................206 9.16.1 Is Arsenicosis or Arsenicism a Mitochondrial Disease? Arsenic and Mitochondria Dysfunction............................................207 9.17 Conclusions....................................................................................................209 References............................................................................................................... 211

9.1 INTRODUCTION Alarming quantities of arsenic in rice, vegetables, sea foods as well as beer and soft drinks render a safeguard to have these consumables. Generally, these problems are concomitant with the enrichment of soil with heavy metal, the quality of water sources used for irrigation, the supply of drinkable water plants, and the intentional use of arsenic compounds for commercial purposes like mineral process and the use of arsenic additives for animal feed to produce more animals in less time at lower cost; generally, the additives are antimicrobial drugs, including arsenicals, antibiotics, etc. Time has demonstrated that mitigation actions must be made. The amount of information about these paradigms, except in the United States and some Asian countries, is scarce. Arsenic causes cancer even at the low levels currently found in our environment. The Evidence also suggests that it contributes to others diseases, including heart 187

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disease [1–5], diabetes [6], and declines brain’s intellectual functioning. Some human exposure to arsenic stems directly from its natural occurrence in the earth’s crust. In some cases arsenic is mined and then used intentionally for commercial purposes and in other cases they come from the mining wastes and metallurgical emissions. As advised by multiple bodies of scientific experts, the United States Environmental Protection Agency (US-EPA) finally lowered its long-outdated drinking water standard in 2001 to that of the World Health Organization’s (WHO) 10 µg/L, that is to say, dropping by fivefold the amount of legally allowed arsenic in tap water. Various Latin American countries like Chile are daily exposed to cancer-causing arsenic that comes from copper mining, drinking water, foods, playground equipment, and from a variety of other sources [7]. Regulatory actions have reduced some of this exposure. However, arsenic also contaminates many of the favorite foods including fish, rice, baby and children foods, animal foods such as that of chicken and swine, vegetables, fruit juices, soft drinks, wine, beer, etc. It is regrettable that some food contamination stems from intentional uses of arsenic.

9.2 ARSENIC CONTAMINATION IN CHICKEN, SWINE, GOAT, AND CATTLE Clearly the presence of arsenic residues in animals that are food for human beings concern, principally, with certain geomedical areas of the earth enriched with arsenic, anthropic contamination of soil, irrigation water, and/or animal feed, but also with the intentional practice of adding arsenic in chicken and swine feed [8–12]. Adding arsenic in chicken feed means exposing more people to arsenic. It is estimated that 1.7–2.2 million pounds of roxarsone, a single arsenic organometallic compound feed additive, are given each year to chickens. Arsenic is an natural endogen element, that is, it does not degrade or disappear and is a persistent pollutant. Arsenic subsequently contaminates much of the 26–55 billion pounds of litter or waste generated each year by the U.S. broiler chicken industry [9]. The average total arsenic in uncooked chicken products purchased in California was in the range of 1.6–21.2 µg/kg, and it appears to be apparent that giving arsenic to chickens further adds to an already elevated arsenic burden in our environment from other intentional uses. Roxarsone, arsanilic acid, nitarsone, and a fourth arsenical called carbarsone are US-FDA approved as feed additives for chickens and turkeys; arsanilic acid is also approved for use in swine feeds. Industry and other sources estimates that at least 1.7–2.2 million pounds of arsenic compounds like roxarsone, that is, almost 1000 tons, are given to broiler chickens in the United States each year. Roxarsonelike compounds can be degraded to other higher toxic metabolites when the excretions of these animals and birds are used as manure, enhancing the uptake of As metabolites by vegetables [13]. Hence, the FDA has set arsenic-tolerance levels in various foods; see Table 9.1. Notice that in chicken livers four times as more arsenic is allowed than breasts, thighs, or other muscle tissues. Most poultry feed additives are not used to treat sickness, rather they are given to healthy birds to promote faster growth on less feed, or prevent diseases. Conventional chicken meat had higher inorganic arsenic concentrations than conventional antibiotic-free and organic chicken meat samples. Cessation of the use of

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TABLE 9.1 U.S. Tolerance Levels for Total Arsenic Residuals in Food

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In eggs and edible tissues of chicken and turkey In edible tissues of swine

500 µg/kg in uncooked muscle tissue 2000 µg/kg in uncooked edible by-products 500 µg/kg in eggs 2000 µg/kg in uncooked liver and kidney 500 µg/kg in uncooked muscle tissue and by-products other than liver and kidney

Source: Wallinga, D., Playing Chicken: Avoiding Arsenic in Your Meat, Institute for Agriculture and Trade Policy Food and Health Program, Minneapolis, MN, 2006, pp. 1–33.

arsenical drugs could reduce the exposure and burden of arsenic-related diseases in chicken consumers [14]. Finally, on September 30, 2013, under the threat of a lawsuit, the US-FDA responded to a nearly 4-year-old petition, calling for the immediate withdrawal of a vast majority of arsenic-containing compounds used as feed additives for chickens, turkeys, and hogs.

9.3 ARSENIC CONTAMINATION IN RICE, CEREALS, FRUITS, AND OTHER VEGETABLE PRODUCTS U.S.-grown rice contains 1.4–5 times more arsenic on average than rice from Europe, India, and Bangladesh. Scientists, think the likely culprit is the American practice of growing rice on former cotton fields contaminated with long-banned arsenic pesticides. Besides, for decades, Americans were exposed intentionally to arsenic from the use of lumbers pressure-treated with chromated copper arsenate (CCA), a pesticide mixture that has 22% arsenic by weight and which is still in use. The United States Environmental Protection Agency (US-EPA) ended its manufacture in 2004. Contamination of shallow groundwater aquifers with arsenic has been reported in over 70 countries around the world [15]. In addition to drinking water health risk, Food and Agriculture Organization (FAO) was concerned about the potential levels of arsenic entering the food chain via absorption by crops from irrigated water. Because rice is the staple food in some Asian countries and is consumed in large quantities, arsenic-contaminated rice could aggravate human health risk when consumed along with drinking water enriched in arsenic. An international symposium held in Dhaka in January 2005 confirmed the presence of high levels of arsenic in irrigated rice and vegetables. Widespread use of As-contaminated irrigation water leads to issues of food security, food safety, and degradation of the environment [16] and to negative impacts such as the following: 1. Reduced agricultural productivity 2. Constraints on land use due to arsenic presence in soils, toxicity of rice, and/or unacceptable quality of agricultural products

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3. Creation of spatial variability in soil As, Fe, Mn, and P levels that makes agricultural management of land difficult 4. Enhanced exposure of humans to As through agricultural products containing elevated levels of arsenic

Rice productivity is affected by soil arsenic, As toxicity interferes with translocation of As from vegetative tissues to grain, that is to say, the grain and straw As concentrations for rice ground in spots and the field yield (ton/ha); wheat yields were negatively correlated with soil As, although it seems unlikely that As was the cause of reduced wheat yield as the concentration of As is low under aerobic soil conditions in which wheat is grown. Irrigation water deposits both As and P in soils, consequently, wheat yield was also negatively correlated with the available P (Olsen method). Also, maize growth and productivity in pots reduced with increasing soil arsenic and grain; arsenic levels were very low in the stem and higher concentrations were found in the leaf than the stem. In Bangladesh, arsenic concentrations in deep tube wells were almost twice (181 µg/L) than the average levels allowed in surface tube wells (0.097 µg/L). In spite of P was also higher in the water of deep tube wells, the more high level of As would accelerate As contamination of soils and exacerbate the food chain and environment As contamination. Deep tube well water, on an average, was also higher in P but lower in Fe and Mn than surface tube well water [16]. Conditions like these are proper of some As enriched ground waters.

9.4  ARSENIC-ENRICHED ENVIRONMENTS Although microorganisms play an essential role in the environmental fate of arsenic in relation to mechanisms of arsenic transformations (e.g., soluble and insoluble forms and toxic and nontoxic forms), human activities have exacerbated arsenic contamination in the environment. Adverse environmental impacts include mining, waste disposal, indiscriminate use of fertilizers, pesticides, herbicides, and manufacturing and chemical spillage. Many incidents of arsenic contamination of the environments have been reported in several countries around the world. Adverse effects on health due to arsenic uptake through water and food is especially high in developing and rural populations that depend on local sources of food and water. Therefore, any arsenic geochemical anomaly may impact negatively on health. Some examples of arsenic-enriched environments are [17] as follows.

9.5  AGRICULTURAL ENVIRONMENTS The dominant source of arsenic in soils is the parent rock, but pesticides and phosphates can enhance arsenic concentration in soils. Arsenic has been used and is still used as pesticides, insecticides, and in cattle and sheep dips and for control of moth in fruit crops. Arsenate portrays certain characteristics of phosphate through its absorption by ligand exchange on hydrous iron and aluminum oxide. Hence, arsenic accumulates in soil, contaminates both surface and groundwater, and is taken up

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by plants and is then entrenched in mammalian–insectivore food chain. Irrigation, especially with wastewater, can cause a problem of buildup of mobile and potentially toxic metals including arsenic in soils and in surface runoff.

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9.6  MINING-RELATED ENVIRONMENTS Mining activities cause arsenic to be released in high concentration from oxidized sulfide minerals. This has resulted in high concentrations of arsenic in surface water, groundwater, soil, and vegetation. In the region of Antofagasta in Chile, it is an serious problem due to volcanism and also because Chilean copper minerals are enriched in arsenic and that copper production in Chile has increased from 700,000 metric tons in 1970 to more than 5,700 metric tons in 2013 [18,19].

9.7  RIVERINE AND VOLCANIC ENVIRONMENTS Volcanoes are important natural sources of arsenic especially in the Southern Hemisphere. Under high temperatures, arsenic is very mobile in the fluid phase and may also be present in fumaroles as sublimates, incrustations, and volcanic ashes increasing arsenic concentrations in water, generating low pH in surface- and groundwater. The coastal–Andean Mountain–Upper Highlands ecosystem of the Antofagasta region in Chile is an important area of the Atacama Desert, of which the River Loa basin is a part. This particular ecosystem suffers from the chronic impact of endogenous arsenic due to volcanism in the area and anthropogenic delivery of arsenic and other heavy metals due to mining activity, which transports trace elements more rapidly into the ecosystem in comparison to the normal geological process, thus spreading the heavy metals to human beings, through the biogeochemical cycles [17,20]. The Loa river suffered five disasters from contamination during the years 1996 and 1998 and in that the most important happened in 1997; the causes were different, but the consequences were similar. Small agricultural towns such as Chíu Chíu, Lasana, and Quillagua were affected majorly and negatively by the contamination and the mining tasks of the proximities were mainly responsible [21,22]. The recent estimation of arsenic in global soils was at 5.0 mg/kg with a mean concentration of 7 mg/kg in surface soils in the United States. Due to the release of arsenic from industrial sources and in mining areas, its concentration in soils can reach 20,000 mg/kg; soil with arsenic levels about 5 mg/kg are considered not contaminated [23], but some actual soil As enrichment depend from their geogenic and anthropogenic As fraction distribution. Without considering the direct discharge of materials, the contamination of soils takes place dominantly due to the emission of inorganic and organic pollutants into the atmosphere and its later immission. A technical difference of the terms pollutant of contaminant is that pollutant is, in general, an environmental stressor that converts it to the category of contaminant when they equal or they overcome primary guidelines of quality and/or secondary or emission guidelines. Pollutants of diverse origins mix in the atmosphere, taking place then the immission, that is to say, the

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descent for graveness and the later soil deposit of these substances or their chemical artifacts, which enter to the biogeochemical cycles of the elements under gases and particulate forms, affecting adversely on men, animals and the environment in general. As particulate material or powder understands each other in the group of materials dispersed in the atmosphere and condensed in solid or liquid form and whose sizes oscillates between 0.05 and 500 µm. A size under 10 µm defines the fractions of breathable particulate material, that is, PM10 and PM2.5, respectively. Usually the particles with environmental connotation are classified, assisting the formation process, into primary that are the direct result of physical or chemical peculiar processes of the source from where they are emitted and secondary that are those that take place starting from chemical reactions in the atmosphere. The classification of sizes has special importance in knowing the dispersion capacity or transport. According to this approach they are distinguished into two categories of particles [24]: • Setting particles, that is to say, those that have a diameter around 5–100 µm at the most, and they reach the soil far from the emission source according to their size. • Particles in suspension or aerosols present inferior diameters less than 5 µm. The particles of small size are controlled by the atmospheric turbulences and wind; their fall speed is very low, since the Brownian movement is worthless, due to which they can be transported to long distances. On the contrary, the particles of large size tend to be similar to the local conditions of the soil, that is to say, with the characteristic emissions of the industrial area feinted by them [24]. Of particular importance for the paradigm of this chapter are the emission-immission tandems for essential elements, heavy metals, hydrocarbons, SO2 and its gas, aerosol and particulate matter artefacts. Recent works carried out in countries like Iran and Jordan that has similar climatic and geographic conditions of desert as that of the area of Antofagasta illustrate with clarity the type of environmental impact that smelting and cement plants produce [25–27]. The gas emissions like NOx and SO2 from the industrial plants can travel long distances and become their corresponding acids, HNO3 and H2SO4, due to the reaction with environmental water (sea breeze, fogs, Camanchaca, rain, etc.) humidity and a phenomenon that is known as acid rain [28]; however, in less humid atmosphere, these gases can also be adsorbed for inorganic particulate materials, also emitted as powders and be fixed directly on the terrestrial surface, and thus precipitating into the soil. The main gas emitted by the smelters is sulfur dioxide (SO2), which is mitigated with added value producing sulfuric acid in plants dedicated for this end. However, a fraction of this gas escapes to the environment, which is transformed into acid fog after chemical transformations or it is adsorbed in finely divided phase minerals that will form salts of sulfates in the soil. On the other hand, SO2 is a powerful reduction agent, but weaker than the sulfhydric acid, with which it reacts and gets oxidized to elementary sulfur. As in Bangladesh, India, Pakistan, Taiwan, China, Hungary, and U.S. Midwest states such as New England, California, and Oklahoma, in many Latin American

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countries such as Argentina, Chile, Bolivia, Peru, and Mexico, at least 14 million people depend on drinking and irrigation water with toxic As concentrations. Also, in Bolivia, Ecuador, Costa Rica, El Salvador, Guatemala, and Nicaragua, As in drinking water has been detected at toxic levels over the last 10–15 years, but the extent of the problem and the number of affected people are still unknown. Sustainable land use and agricultural practices in Latin American countries are threatened by the use of irrigation water with high arsenic contents. However, only Chile, Peru, and Mexico have a few available but incomplete studies on the contamination of soils, crops, and animal fodder in the region. Despite the relative lack of availability of detailed data, it is estimated that at least 4.5 million people in Latin America are currently drinking arsenic-contaminated water ranged 50–2000 µg/L, that is to say, 200 times higher than the current WHO standard (10 µg/L) for drinking water [29]. In Tables 9.2 and 9.3, details of metal contents in corn in San Salvador River area and other vegetables in Chiu-Chiu, Calama, Chile, is presented [30]. Arsenic speciation in vegetables and fruits samples are dominated by inorganic arsenic, that is to say, Arsenate (As5+) and Arsenite (As3+) [31]. Arsenic was first documented by Albertus Magnus in AD 1250; but at present we cannot forget “we are what we drink, we eat, and we breathe”; the chronic human exposure to arsenic causes a number of adverse health effects, including among others cardiovascular and neurologic pathologies and several types of cancer [32,33]. Therefore, the WHO standard for drinking water is a critical parameter and presently the world needs to take urgent measures to limit the values of arsenic, termed as a silent global poison, in foods and alcoholic drinks, in particular the wines, soft drinks, and fruit juices, to safely allowed limits and mitigate its impact on the quality of healthy life. In the twenty-first century, arsenic continues being a global calamity [34,35], one of which few governments speak, but only the scientists concerned about healthy human life doing it.

TABLE 9.2 Meana of the Total Residual Heavy Metal Concentrations in Teeth and Cores of Corns from Sector San Salvador River in Calama, Chile Element

Core

Teeth

Cu Zn Cd Pb Hg As Se

2.02 13.4 0.087 0.17 0.018 2.58 0.79

4.16 13.5 0.086 0.22 0.027 3.31 0.72

Source: Román, D.A. and Román, H.A., Agreement of Collaboration between University of Antofagasta Technical Attendance, Agricultural and Cattle Service, Antofagasta, Chile, 2004. a µg/g, wet weight.

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TABLE 9.3 Mean and Concentration Factors (Chilean/Spain) of Total Residual Heavy Metal Concentrations in Lyophilized Carrots, Beets, and Quinoa from Chiu-Chiu, Calama, Chile Vegetables

As (µg/g)

Cd (µg/g)

Pb (µg/g)

Cu (µg/g)

Carrots Flesh—Ca Flesh—Cb Flesh—Sa Factor Peel—Ca Peel—Sa Factor

0.52 ± 0.04 0.54 ± 0.06 0.02 ± 0.01 24 1.62 ± 0.05 0.15 ± 0.01 11

0.05 ± 0.01

0.12 ± 0.02

7.75 ± 0.91

4.75 ± 0.51

0.07 ± 0.01 0.7 0.08 ± 0.01 0.12 ± 0.02 0.7

0.09 ± 0.01 1.3 0.21 ± 0.02 0.23 ± 0.03 0.9

8.82 ± 0.59 0.9 16.3 ± 1.50 17.30 ± 0.9 0.9

2.28 ± 0.18 2 9.95 ± 0.20 13.70 ± 0.9 0.7

Beets Flesh—Ca Flesh—Cb Flesh—Sa Factor Peel—Ca Peel—Sa Factor Quinoa—Ca Quinoa—Cb Quinoa—C [30] Factor

0.62 ± 0.05 0.64 ± 0.07 0.02 ± 0.00 26 3.20 ± 0.06 0.22 ± 0.01 14 0.20 ± 0.02 0.21 ± 0.04 0.01 ± 0.01 20

0.09 ± 0.00

0.36 ± 0.01

6.71 ± 0.95

8.38 ± 0.16

0.05 ± 0.00 1.8 0.11 ± 0.01 0.03 ± 0.01 3.6 0.38 ± 0.07