Contamination in Foods

In companion publications, pesticides were sampled with a laser desorbed vapors were passed into a differential mobility spectrometer (DMS). Fast detection of pesticides was made using apples, grapes, tomatoes, and peppers, with detection limits in the nanogram range. The detection of pesticides was improved for DMS with an atmospheric pressure photoionization ion source modified with dopants such as benzene, anisole, and chlorobenzene. Improvements of detection limits up to two orders of magnitude were observed, and peaks were displaced on the compensation voltage (CV), axis as expected with modified gas atmospheres in DMS. 

A last example of IMS methods applied to food quality is the determination of aflatoxins B1 and B2 on pistachio samples methanol extracts of samples were introduced into an IMS analyzer equipped with an IMS equipped with a nonradioactive, corona discharge ion source. The response to aflatoxins was acceptable for screening purposes, with a linear range of roughly 100, relative standard deviations 10% or lower, and a limit of detection of 0.25 ng for both aflatoxins. Ammonia could be used as a dopant, and detection limits were improved by a factor of 2.5. Authentic pistachio samples were analyzed without difficulties. 

In comparison to previous summaries of industrial applications of IMS, the discussion here illustrated a wide breadth of applications in the past decade. In addition, significant depth is seen, with methods applied in actual online process control, monitoring of stacks, ambient air monitoring, and measurements with authentic samples, not only standard laboratory solutions. The versatility and capability of IMS are now proven in the range of chanicals monitored, the complex matrices for some samples, and the demands on instruments. The advantages of IMS include reliability and quantitative performance, speed of response, durability in accepting sample with little preparation, and low detection limits. When samples are complex enough to create complications from competitive reactions in the ion source, remedies have been found with fast GC or temperature-ramped desorption of sorbent traps. 

Pilzecker, R Bamnbach, J.I. Kurte, R., Detection of decomposition products in SF a comparison of colorimetric detector tubes and ion mobility spectrometry. Proceedings of the Conference on Electrical Insulation and Dielectric Phenomena, 2002, 865-868 DOI 10.1109/CEIDP.2002.1048932. 

Baumbach, J.I. PUzecker, P. Trindade, E., Monitoring of circuit breakers using ion mobility spectrometry to detect SFg-decomposition, Int. J. Ion Mobil. Spectrom. 1999, 2, 35-39. 

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Golberg, L., Trace chemical contaminants in food potential for harm, ... 

J.N. Seiber, Analysis of chemical toxicants and contaminants in foods, in Food Toxicology, ed. W. Helferich and C. K. Winter, CRC Press, Boca Raton, FL, Chapt. 9 (2001). 

During the last few years, miniaturization has become a dominant trend in the analysis of low-level contaminants in food and environmental samples. This has resulted in a significant reduction in the volume of hazardous and expensive solvents. Typical examples of miniaturization in sample preparation techniques are micro liquid/liquid extractions (in-vial) and solvent-free techniques such as solid-phase microextraction (SPME). Combined with state-of-the-art analytical instrumentation, this trend has resulted in faster analyses, higher sample throughputs and lower solvent consumption, whilst maintaining or even increasing assay sensitivity. 

From these data, it is clear, for example, that in spite of being banned in agriculture in 1970, DDT contaminated food products on an especially wide scale for some time. HCH contamination in food products was just as high, but it had yet to be banned. Extreme contamination, i.e. that exceeded MPL by more than five times, occurred in at least six samples of the same product (Table 3.16). 

Flegal AR, Smith DR, Elias RW. 1990. Lead contamination in food. Adv Environ Sci Technol 23 85-120. 

EC (European Commission) (2002a), Commission Regulation No 472/2002 of 12 March 2002 amending regulation (EC) No 466/2001 setting maximum limits for certain contaminants in food stuffs , Official J. Europ. Union, L77, 1-13. 

This document deals only with estimating exposure to direct additives and chemical contaminants. The procedures used to estimate exposure to chemical contaminants in food (including naturally occurring toxicants, such as mycotoxins) are essentially the same as those used for direct additives. Thus, contaminants will be considered in the discussion of direct additive exposure estimation. The procedures discussed herein are equally applicable to color additives, GRAS substances, prior-sanctioned ingredients, and pesticide residues. 

WHO (1987). Principles for the Safety Assessment of Food Additives and Contaminants in Food. Environmental Health Criteria 70. World Health Organisation, Geneva. 

This volume provides comprehensive information about contaminants in the food industry. The book opens with an explanation of risk analysis and analytical methods used for detecting contaminants in food products. This is followed by full details of relevant EU and USA regulations. The second part of the book provides information about specific contaminants. 

Dietary exposure of dioxin and source directed measure to reduce its contamination in food (ZHUANG Zhixiong, China)... 

So far, LSE is the most popular for extracting contaminants in food. However, over the last years LPME in its different application modes (single drop microextraction, dispersive liquid-liquid microextraction and hollow fiber-LPME) has been increasingly applied to food analysis because of its simplicity, effectiveness, rapidity, and low consumption of organic solvents. Different applications have been recently reviewed by Asensio-Ramos et al. [112]... 

The characterisation of health hazards of food contaminants, the assessment of the occurrence of undesirable compounds in food and the estimation of the dietary intake are key issues in the risk assessment. In 2000, the European Commission published a White Paper on Food Safety, which underlined the importance of ensuring the highest possible standards of food safety and proposed a new approach to achieve them. Recently, PFCs have gained increased scientific and socioeconomic interest as emerging environmental contaminants due to the unique combination of persistence, toxicity and environmental prevalence. Risk assessment of the dietary exposure to PFCs, however, is hampered by the lack of sufficient data about the occurrence of these contaminants in food. 

Bioaccumulation is generally referred to as a process in which the chemical concentration in an organism achieves a level that exceeds that in the respiratory medium (e.g., water for a fish or air for a mammal), the diet, or both. The extent to which chemicals bioaccumulate is expressed by several quantities, including the bioconcentration factor (BCF), bioaccumulation factor (BAF), biomagnification factor (BMF), and trophic or food web magnification factor (TMF) [6]. The ecological, biological and chemical parameters involved in the transfer and accumulation of contaminants in food webs are complex. 

Page DB, Lacroix GM. 1995. On-line distillation/purge and trap analysis of halogenated, nonpolar, volatile contaminants in foods. J AOAC Int 78(6) 1416-1428. 

The term Tolerable is used for agents, which are not deliberately added such as contaminants in food. 

WHO/IPCS. 1987. Principles for the safety assessment of food additives and contaminants in food. Environmental Health Criteria 70. Geneva WHO. http //www.inchem.org/documents/ehc/ehc/ehc70.htm... 

The US-EPA is the federal agency responsible for standard settings in relation to contaminants in ambient air (Section 9.2.2.1), drinking water (Section 9.2.2.2), and soil (Section 9.2.2.3) while the U.S. Pood and Drug Administration (US-FDA) is the federal agency responsible for standard settings in relation to contaminants in food (Section 9.2.2.4). 

The US-FDA is the federal agency responsible for regulating the level of contaminants in food (US-FDA 2007). The US-FDA establishes action levels for poisonous or deleterious substances to control levels of contaminants in human food and animal feed. 

While there are standards for lead exposure, at this time there is no level that is considered safe, so the best policy is to avoid lead exposure. This is difficult because as a contaminant in food, water, or dust, lead cannot be seen, tasted, or smelled. 

Data and information about a substance submitted as part of the procedures for establishing a tolerance for unavoidable contaminants in food and food-packaging materials, described in parts 109 and 509. 

Hothem, R.L. and H.M. Ohlendorf. 1989. Contaminants in foods of aquatic birds at Kesterson Reservoir, California, 1985. Arch. Environ. Contam. Toxicol. 18 773-786. 

Food additives and contaminants in food, principles for the satiety assessment of (No. 70,1987)... 

The International Programme on Chemical Safety (IPCS) is a joint venture of the United Nations Environment Programme, the International Labour Organization, and the World Health Organization. The IPCS evaluates the effects of chemicals on human health and the environment. A joint publication by the IPCS and JECFA, Principles for the Safety Assessment of Food Additives and Contaminants in Food (8), discusses the testing of chemicals used in foods, the evaluation of the test results, and the general basic set of data requirements necessary to evaluate food additives and contaminants. 

As mentioned above, this unique method can be used to detect and identify volatile contaminants in food materials. As shown in chromatogram A in Figure 5, raw peanuts that had been in a cardboard box in the laboratory yielded relatively large... 

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