Decabromodifenyl Ether (BDE-209) in Surface Soils from Warsaw and Surrounding Areas: Characterization of Non-Carcinogenic Risk Associated with Oral and Dermal Exposure

Polybrominated diphenyl ethers (PBDEs) have been used for many years as flame retardants. Due to their physicochemical and toxicological properties, they are considered to be persistent organic pollutants (POPs). BDE-209 is the main component of deca-BDE, the one PBDE commercial mixture currently approved for use in the European Union. The aim of this study was to analyse BDE-209 in surface soil samples from Warsaw and surrounding areas (Poland) as an indicator of environmental pollution with PBDEs, and to characterise the associated health risk. A total of 40 samples were analysed using gas chromatography with electron capture detection (GC-µECD). Concentrations of BDE-209 in soil ranged from 0.4 ng g-1 d.w. (limit of quantification) to 158 ng g-1 d.w. Overall, 52.5% of results were above the method's limit of quantification. The highest levels were found at several locations with heavy traffic and in the vicinity of a CHP plant in the city. The lowest concentrations were observed in most of the samples collected from low industrialized or green areas (<0.4 to 1.68 ng g-1 d.w.). Exposure to BDE-209 was estimated for one of the most sensitive populations, i.e., young children. The following exposure routes were selected: oral and dermal. No risk was found to young children's health.

Assessment of Furan and Its Derivatives Intake with Home Prepared Meals and Characterization of Associated Risk for Polish Infants and Toddlers

Furan and its derivatives are found in various heat-treated foods. Furan is classified as a possible human carcinogen. The European Union authorities recommend collecting data on the occurrence of these compounds, estimating consumer exposure, and taking measures to protect human health based on a scientific risk assessment. The aim of this study was to estimate the exposure of infants and toddlers to furan and its methyl derivatives-2-methylfuran, 3-methylfuran, and ∑2,5-dimethylfuran/2-ethylfuran-present in home-prepared foods and to characterize the associated health risks. The compounds of interest were determined using the HS-GC/MS. The risk was characterized by the calculation of the margin of exposure (MoE). Levels of furan and its derivatives in analyzed samples were in the range of Collapse

Key Words

• exposure
• furan
• furan derivatives
• health risk characterization
• home-prepared meals
• infants
• toddlers

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MESH Headings Collapse

Grants

• 1BTBW/2019, FT-1/2020 National Institute of Public Health NIH - National Research Institute

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Validation of a Modified QuEChERS Method for the Determination of Selected Organochlorine Compounds in Honey

Honey is considered to be a health-promoting food product. Therefore, it is assumed that it should be free of contaminants. Although the use of organochlorine pesticides (OCPs) was banned a few decades ago in developed countries, persistent organic pollutants (POPs) are still detected in various environmental and biological matrices, including food. These contaminants exhibit toxic properties and bioaccumulate in some food chains. The validation of a modified QuEChERS extraction method was successfully performed for o,p'-DDT, o,p'-DDE, o,p'-DDD, p,p'-DDT, p,p'-DDE, p,p'-DDD, heptachlor and dieldrin. 2,2',4,4',5,5'-hexachlorobiphenyl (PCB 153) was used as an internal standard. The modification involved changing the solvent from acetonitrile to n-hexane after extraction. Quantitation was carried out using gas chromatography with an electron capture detector (µECD). The mean recovery values for o,p'-DDT, o,p'-DDE, o,p'-DDD, p,p'-DDT, p,p'-DDE, p,p'-DDD and dieldrin, spiked at 2.9 ng/g and 20 ng/g, ranged from 64.7% to 129.3%, and, for heptachlor spiked at 5.6 ng/g and 20 ng/g, ranged from 68.0% to 88.3%. The relative standard deviation (RSD) for these concentrations did not exceed 20%, and the within-laboratory reproducibility was below 20%, except o,p'-DDE and p,p'-DDT, which were 25.2% and 20.7%, respectively. This modified QuEChERS extraction method for selected organochlorine compounds was demonstrated as effective for routine testing in honey.

A novel method for rapid and quantitative detection of bisphenol A in urine

Bisphenol A (BPA) is classified as an endocrine disruptor (ED) and it can interact with variety of hormone receptors leading to hormonal disruption and increased risk of various adverse health effects. Reducing human exposure to BPA is one of the main challenges of public health, as it is constantly present in daily life. A low-cost and commonly applied method to enable determination of BPA in the patient's body has yet to be developed. Currently available techniques are expensive, time-consuming, and require access to highly equipped analytical chemistry laboratories. Here we describe a fast and cheap engineered lateral flow assay of our design, to detect of BPA in urine samples. The technology not only provides an opportunity to perform rapid medical diagnostics without the need for an access to the central laboratory but also a means for self-diagnosis by the patient. The addition of β-glucuronidase improves the sensitivity of detection as it releases the free BPA from glucuronide complexes in urine. This invention may become a demonstrated analytical means for lowering human exposure to BPA and probably also to other EDs and consequently, may be useful in decrease of the risk for several lifestyle diseases.

Levels of polybrominated diphenyl ethers in house dust in Central Poland

Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in numerous products, from which they are emitted to the environment, including house dust. House dust is a source of human exposure to these compounds by ingestion. The aim of this article was to determine the levels of selected PBDEs in the house dust and indicate their potential sources of origin. PBDE congeners: BDE-47, BDE-99, BDE-153 and BDE-209, were analyzed in 129 samples. The geometric mean levels (and 95% CIs) of the aforementioned congeners amounted to 3.8 (3.1-4.7) ng/g, 4.5 (3.5-5.6) ng/g, 2.2 (2.1-2.4) ng/g and 345 (269-442) ng/g respectively. BDE-209 was the dominant congener in the majority of tested samples. We found a statistically significant correlation between the concentrations of BDE-47 and the computer operating time per day (r_s - 0.18) and the living area (r_s - 0.20). Statistically significant higher levels of BDE-99 were found in homes where the floor was not replaced during the last 2 years.

Exposure to persistent organic pollutants and sperm DNA methylation changes in Arctic and European populations

Persistent organic pollutants (POPs), such as PCBs (polychlorinated biphenyls) and DDT [1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane], are environmental contaminants with potential endocrine disrupting activity. DNA methylation levels in peripheral blood lymphocytes have been associated with serum concentrations of POPs in Greenland Inuit and Korean populations. Greenland Inuits are characterized by the highest worldwide POP levels. In this cross-sectional study we evaluated the relationship between serum POP concentrations and DNA methylation levels in sperm of non-occupationally exposed fertile men from Greenland, Warsaw (Poland), and Kharkiv (Ukraine). Serum levels of PCB-153 [1,2,4-trichloro-5-(2,4,5-trichlorophenyl)benzene], as a proxy of the total PCBs body burden, and of p,p'-DDE [1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene], the main metabolite of DDT were measured. Sperm DNA methylation level was assessed globally by flow cytometric (FCM) immunodetection of 5-methyl-cytosines and at specific repetitive DNA sequences (Alu, LINE-1, Satα) by PCR-pyrosequencing after bisulfite conversion. Multivariate linear regression analysis was applied to investigate correlations between serum POP concentrations and DNA methylation. No consistent associations between exposure to POPs and sperm DNA methylation at repetitive DNA sequences were detected. A statistically significant global decrease in methylation was associated with exposure to either POP by FCM analysis. This is the first study to investigate environmental exposure to POPs and DNA methylation levels considering sperm as the target cells. Although POP exposure appears to have a limited negative impact on sperm DNA methylation levels in adult males, the global hypomethylation detected by one of the methods applied suggests that further investigation is warranted.

Validation of the analytical method for the simultaneous determination of selected polybrominated diphenyl ethers, polychlorinated biphenyls and organochlorine pesticides in human blood serum by gas chromatography with microelectron capture detector

BACKGROUND

Polybrominated diphenyl ethers (PBDEs) as other persistent organic pollutants like polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) pose a significant hazard to human health, mainly due to interference with the endocrine system and carcinogenetic effects. Humans are exposed to these substances mainly through a food of animal origin. These pollutants are globally detected in human matrices which requires to dispose reliable and simple analytical method that would enable further studies to assess the exposure of specific human populations to these compounds.

OBJECTIVE

The purpose of this study was to modify and validate of the analytical procedure for the simultaneous determination of selected PBDEs, PCBs and OCPs in human blood serum samples.

MATERIAL AND METHODS

The analytical measurement was performed by GC-µECD following preparation of serum samples (denaturation, multiple extraction, lipid removal). Identity of the compounds was confirmed by GC-MS.

RESULTS

The method was characterised by the appropriate linearity, good repeatability (CV below 20%). The recoveries ranged from 52.9 to 125.0% depending on compound and level of fortification. The limit of quantification was set at 0.03 ng mL(-1) of serum.

CONCLUSIONS

The modified analytical method proved to be suitable for the simultaneous determination of selected PBDEs, PCBs and OCPs in human blood serum by GC-µECD with good precision.

Dioxins, furans, and polychlorinated biphenyls in hen eggs – a new source of hazard for consumers?

The paper presents the results of testing eggs for the content of dioxins and polychlorinated biphenyls (PCBs), determination of the sources that caused the presence of high concentrations of these compounds which exceeded the acceptable contamination levels, and assessment of consumer health risk caused by the consumption of eggs with excessive contents of investigated compounds. In about 9% of free range eggs and 17% of organic eggs, the content of PCDD/Fs was two- or threefold higher than the acceptable limits, and in some samples the concentration of investigated compounds exceeded the maximum concentration levels. Based on the profile of the compounds, it was confirmed in several cases that their main source was the soil or unsecured refuse. The consumers of eggs and meat produced under these conditions constitute the risk groups, and their dioxin and PCB intake may exceed toxicological reference values.

Perfluorinated chemicals in blood serum of inhabitants in central Poland in relation to gender and age

The goal of this paper is to determine concentrations of seven selected perfluoroalkylated substances (PFASs): perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorododecanoic acid (PFDoDA) in the blood serum of men and women of reproductive age from the central region of Poland. The relation between sex of tested subjects and the levels of compounds in blood serum of humans will also be considered and analysed as an element of the risk assessment. The study was made on the blood serum samples collected from 253 women and 176 men of reproductive age between 20 and 44 years from Warsaw and surrounding areas. Higher concentrations of five (PFOS, PFOA, PFNA, PFDA, PFUnDA) from among seven selected PFASs were observed in men in comparison to women from the same populations. Only the concentrations of PFHxS and PFDoDA were slightly higher in women than in men. These differences were statistically significant in all cases, except for PFUnDA. The hypothesis that the concentrations of said compounds increase with age of the test subjects, regardless of gender has not been confirmed.

Biopesticides--towards increased consumer safety in the European Union

The introduction of new food safety regulations in the European Union has resulted in the withdrawal of many synthetic active substances used in plant protection products, in light of their potential or actual harmful effect on human and animal health, as well as on the environment. Alternatives to these compounds are being developed - naturally occurring pesticides, also referred to as biopesticides. The use of biopesticides in crop protection leads to decreased levels of pesticide residues in foods, and as a result to lower risk levels for the consumer. Biologically active agents defined as biopesticides are varied, and therefore application of the same environmental and consumer safety criteria to all of them is impossible. This presents serious complications in the approval of these pesticides as active plant protection products and in their registration. It needs to be stressed that, in the registration procedure of the European Union, biopesticides are subject to the same regulations as synthetic active substances. This situation has resulted in the need to introduce numerous new provisions in the legislation, as well as the preparation of new guidelines facilitating the registration of biopesticides. These activities aim to promote naturally originating pesticides.

Hazard quotient profiles used as a risk assessment tool for PFOS and PFOA serum levels in three distinctive European populations

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) blood levels are commonly used as biomarkers of human environmental exposure to these compounds. Many biomonitoring studies indicate 100% detection for PFOS and PFOA thus justifying a concern of possible risk for the most exposed individuals. This study addresses the predictive value of hazard quotients (HQs) calculated on the basis of serum PFOS and PFOA in male and female populations of reproductive age in Greenland, Poland and Ukraine. Overall, 2026 results of PFOS and PFOA serum concentrations (589 males, 1437 females) were obtained from the INUENDO database. HQs were calculated from the actual biomonitoring results and literature-based animal data linking toxicological outcomes and critical PFOS/PFOA serum levels. HQs for serum PFOS were calculated based on Points of Departure (PoD) at 13μgmL(-1) (cynomolgus monkeys, 183days, changes in THS and T3) and for PFOA at 7.1μgmL(-1) serum (male rats, 90days, hepatocellular necrosis, increased liver weight). Uncertainty factors were applied to reflect interspecies differences and human variability. Serum HQs were expressed as a ratio relative to the point of departure for each PFOS and PFOA. Only in the three cases of males in Greenland were there serum PFOS levels showing HQ values exceeding 1, so indicating that such serum levels may be of concern. The mean serum concentration of PFOS was significantly higher in male than in female populations. Despite significant differences between HQ profiles for PFOS and PFOA in donors from Greenland, Poland and Ukraine, the concentrations of these perfluoroalkylated compounds do not indicate a cause for concern, except for the three aforementioned cases from Greenland. This study demonstrates that the HQ approach can help to interpret human biomonitoring data and thus serve as a valuable tool in further risk assessment priority settings and may also be used as a basis for taking decisions in risk management.

Risk assessment for pesticides' MRL non-compliances in Poland in the years 2011-2015

BACKGROUND

Human exposure to trace levels of pesticide residues present in food of plant origin is inevitable as long as pesticides continue to be applied in agriculture. Since Maximum Residue Levels (MRL) are not toxicological endpoint values, their violation is not by default equivalent to health risk for consumers. However, its essential to provide a health- based risk assessment for each case of MRL non-compliance reported during monitoring and official control of foodstuffs.

OBJECTIVE

To assess the potential short-term risk associated with consumption of food products of plant origin containing pesticide residues above MRL values based on notifications forwarded by the National Contact Point for RASFF in Poland during 2011-2015.

MATERIAL AND METHODS

115 notifications including 127 analytical results non-compliant with respective MRL values were forwarded to provide risk assessment. An internationally accepted deterministic approach based on conservative model assumptions for short-term exposure assessment was applied. The risk was characterized by comparing an estimated dietary intake with respective acute reference dose (ARfD).

RESULTS

Black currant, tea, lettuce, Chinese cabbage and carrot were among the most frequently notified products in years 2011-2015. Among pesticides exceeding respective MRL values, over 90% belonged to fungicides and insecticides/acaricides such as acetamiprid, chlorpyrifos, dimethoate, imidacloprid, dithiocarbamates and procymidone. For 15 and 6 results noncompliant with respective MRL value, a predicted short-term intake exceeded ARfD for children and adults, respectively.

CONCLUSIONS

Residue levels that could potentially pose a health threat are found incidentally. The science-based and transparent risk assessment process with regard to the data, methods and assumptions that are applied is essential to risk management authorities.

KEY WORDS

risk assessment, pesticide residues, MRL, dietary intake, RASFF, food safety.

Development and validation of a method for determination of selected polybrominated diphenyl ether congeners in household dust

BACKGROUND

Polybrominated diphenyl ethers (PBDEs) belong to group of so-called persistent organic pollutants (POPs). These compounds occur in nearly all elements of the environment, including household dust which constitutes one of a major route for human exposure. Their main adverse effects on human health are associated mainly with endocrine disruption--they interfere with thyroid function exhibit anti-androgenic action.

OBJECTIVES

To develop and validate analytical method for determination of BDE-47, BDE-99, BDE-153, and BDE-209 congeners in household dust.

MATERIAL AND METHODS

Household dust was sampled in residences from Warsaw and the surrounding areas. An automated Soxhlet extraction of samples was then performed and PBDE congeners were subsequently measured in cleaned-up extracts by GC-microECD. The identity of quantified compounds was confirmed by GC/MS.

RESULTS

Household dust samples were fortified at levels of 2.88, and 28.8 ng g(-1) for BDE-47, BDE-999, and BDE-153, and for BDE-209 at levels of 101.2, and 540 ng g(-1). Recoveries ranged between 72 - 106%. The relative standard deviations (RSD) were less than 16% for all PBDE congeners analysed. The relative error determined on the basis of multiple analyses of certified reference material ranged from 1.07 - 20.41%. The method's relative expanded uncertainty varied between 16 - 21%.

CONCLUSION

The presented method was successfully validated and can be used to measure concentrations of BDE-47, BDE-99, BDE-153 and BDE-209 congeners in household dust.

Characterising the individual health risk in infants exposed to organochlorine pesticides via breast milk by applying appropriate margins of safety derived from estimated daily intakes

Milk secretion being an important way of elimination of organochlorine pesticides (OCPs) poses a concern due to potential risk for breastfed infants. This study aims to provide a tool for assessing such risks to infants exposed to OCPs (through accumulation in the mother's body), using calculated individual margins of safety (MoS). Selected OCPs included; p,p'-DDT, p,p'-DDD, p,p'-DDE, β-HCH, γ-HCH and HCB which were analysed in 28 samples of maternal milk. The highest intakes were recorded for p,p'-DDE (at 2.90 μg kg(-1)bw d(-1)) whilst the lowest was for γ-HCH, (at 0.019 μg kg(-1)bwd(-1)). For the risk characterisation purposes MoSs were calculated for the compounds for which toxicological reference values (e.g. ADI, TDI) were adopted. The MoS for average ∑DDT concentrations was found to be relatively low (2.82) somewhat similar to that for HCB at 7.08, and for γ-HCH, the MoS was substantially higher at 263.1. This, however does not take into account the extremely high individual concentrations. Thus, it was decided to calculate estimated daily intake (EDI) values based on OCP levels in individual milk samples. MoS levels of <1 (meaning unacceptable risk) were noted both for HCB in one sample as well as for ∑DDT in 3 samples indicating likely threats to infant's health. The lowest MoS noted for γ-HCH equalled to 60.6, indicating that this compound was not a threat to the health of any of the breastfed infants from the study group.

Polybrominated diphenyl ethers and polychlorinated biphenyls in cord blood from women in Poland

The purpose of this study was to assess human exposure in the prenatal period to selected PBDEs (BDE-47, BDE-99, BDE-153) and PCBs (CB-77, CB-101, CB-118, CB-126, CB-138, CB-153, CB-170, CB-180) basing on the analysis of these compounds in cord blood. The experimental material consisted of 89 cord blood samples taken from women resident in Warsaw and its vicinity. In over 90% of all tested samples the presence of congeners CB-153, CB-138, CB-180 and BDE-47 was identified. The least frequently found were CB-126 and BDE-153, which were present at relatively low concentration levels. Among all analysed PCBs, the highest average concentrations were found in the case of congeners CB-138 (11.8 ng/g of fat) and CB-153 (43.4 ng/g of fat), whereas the lowest was in the case of CB-170 (0.4 ng/g of fat) and CB-126 (0.1 ng/g of fat). In the case of PBDEs the greatest share in the total concentration was that of the congeners BDE-47 and BDE-99, whereas the smallest share was that of the higher brominated congener BDE-153. These results suggest that human exposure to the examined compounds begins already in the period of intrauterine life. The comparison of our own results with the findings of other authors indicates that the PCBs and PBDEs levels in cord blood of women living in Poland do not differ from the respective concentrations in cord blood of other female inhabitants of Europe.

PCDD/Fs and DL-PCBs intake from fish caught in Polish fishing grounds in the Baltic Sea--characterizing the risk for consumers

Fish and fishery products are among the primary sources of dietary exposure to dioxins. It is known that some fish species caught in the Baltic Sea contain elevated level of those compounds. Levels of dioxins and DL-PCBs in 236 Baltic fish samples (including 65 salmon, 14 sea trout, 63 sprat, 63 herring, 31 cod), and 20 cod liver samples from the Polish fishing grounds (the ICES zones 24-27), collected in the time frame of 2006-2011 as part of Polish monitoring survey have been used for risk assessment. To characterize potential health risk associated with dioxins intake, doses ingested in a single portion of fish and cod liver by adults (200g for fish, 125g for cod liver), and children (100g for fish, 25g for cod liver) were expressed as percent of Tolerable Weekly Intake (TWI) and Provisional Tolerable Monthly Intake (PTMI). Average dioxins intake estimated for fatty fish species was about 250% TWI for children, and about 170% TWI for adults, with maximum values of 436.3 and 288.0% TWI, respectively. Maximum exposure expressed as percent of PTMI was below 90% for children and below 60% in adults. For sprat and herring, mean dioxins intakes were lower, but still not at "safe" level: 100-150% TWI for children and about 70-100% for adults, with the maximum values of about 250 and 180%, respectively. Maximum exposure expressed as percent of PTMI was approximately 50% for children and 35% for adults. Intakes values calculated for practically "dioxin-free" cod are just theoretical because in calculating toxic equivalents (TEQs) an upperbound approach was applied, and vast majority of TEQs originates from the limit of quantification (LOQ) values of all non-quantified congeners. Frequent consumption of cod liver seems to be a health risk as, according to assumed scenario, dioxins intake of 100% PTMI for adults would be achieved by the 65th percentile, while for children by approximately 90th percentile of results. Serving sizes of salmonids, cod liver, and even sprat, and herring that lead to total dioxins intake equal to TWI, and PTMI were relatively small. Thus, one can easily exceed those toxicological reference values consuming above Baltic fish species available on the Polish market. Taking into account low fish consumption in Poland and, additionally, low share of Baltic fish in total consumption of marine fish, potential risk of high dioxins intake does not apply to general population. Occasionally elevated dioxins intake above TWI or PTMI is not necessarily related to health risk, because of uncertainty factors embedded in these toxicological reference values. However, some sub-populations in Poland that habitually consume fatty fish originating from the Baltic Sea or Baltic cod liver may be at an elevated health risk of potential consequences of chronic exposure to dioxins. Dietary recommendations based on risk-benefit analysis for consumers of such fish and fishery products from the Baltic Sea would be the most effective tool for risk management.

[Indoor dust as a pathway of human exposure to polybrominated diphenyl ethers (PBDEs)]

The brominated diphenyl ethers (PBDEs) belong to a class of synthetic, additive brominated flame retardants (BFRs). PBDEs are used to reduce the flammability of commercial and household products such as textiles, various plastic polymers, furnishing foam, and electronic equipment. People spend a large percentage of their life-time indoors at home, in offices and cars, etc, providing many opportunities for lengthy exposure to PBDEs from residential settings and commercial products in an indoor environment. In recent time, the foodstuffs, mainly food of animal origin, have been indicated as the main pathway of human exposure to PBDEs. However, many studies have shown that the indoor environment, mainly indoor dust, can be also a significant source of exposure to PBDEs, especially for younger children (toddlers) because of their behavioral patterns, eg. putting fingers, toys, and other items in their mouth. Numerous studies show that the median intakes of PBDEs via dust for adult range from 1.41 to 277 ng x day(-1) is lower than that via food which range from 135 to 333 ng x day-', while the median intake of these compounds via indoor dust for children range from 101 to 404 ng x day(-1) is much higher than via food: 77-190 ng x day(-1). The congener pattern observed in the indoor dust is different to that found in food. The indoor dust is dominated by the congener BDE-209 vs. food where the most dominated congeners are BDE-47 and BDE-99. Human exposure to PBDEs and other brominated flame retardants (BFRs) is widely widespread throughout the world and it depends on a country range of usage, production and legislation concerning these chemicals as well as a citizen's behavior. Generally, human exposure has been found higher in North America than in Europe and Asia. Within European countries the significant highest concentrations in dust have been found in the United Kingdom. It should be noted that many uncertainty factors such as personal habits, dietary preferences, and time spent in various rooms, cars and outdoors could affect the exposure assessment. In some cases the occupational exposure is the most important source of PBDEs for adults, for example air crews, car sale employees and disposal/recycling of electronic waste workers.

Risk assessment for infants exposed to furan from ready-to-eat thermally processed food products in Poland

BACKGROUND

Thermal processes and long storage of food lead to reactions between reducing sugars and amino acids, or with ascorbic acid, carbohydrates or polyunsaturated fatty acids. As a result of these reactions, new compounds are created. One of these compounds having an adverse effect on human health is furan.

OBJECTIVE

The aim of this paper was to estimate the infants exposure to furan found in thermally processed jarred food products, as well as characterizing the risk by comparing the exposure to the reference dose (RfD) and calculating margins of exposure.

MATERIALS AND METHODS

The material consisted of 301 samples of thermally processed food for infants taken from the Polish market in years 2008 - 2010. The samples included vegetable-meat, vegetables and fruit jarred meals for infants and young children in which the furan levels were analyzed by GC/MS technique. The exposure to furan has been assessed for the 3, 4, 6, 9,12 months old infants using different consumption scenarios.

RESULTS

The levels of furan ranged from <1 microg/kg (LOQ) to 166.9 microg/kg. The average furan concentration in all samples was 40.2 microg/kg. The estimated exposures, calculated with different nutrition scenarios, were in the range from 0.03 to 3.56 microg/kg bw/day and exceeded in some cases RfD set at level of 1 microg/kg bw/day. Margins of exposure (MOE) achieved values even below 300 for scenarios assuming higher consumption of vegetable and vegetable-meat products.

CONCLUSIONS

The magnitude of exposure to furan present in ready-to-eat meals among Polish infants is similar to data reported previously in other European countries but slightly higher than indicated in the recent EFSA report. As for some cases the estimated intake exceeds the RfD, and MOE) values are much lower than 10000 indicating a potential health concern, it is necessary to continue monitoring of furan in jarred food and estimate of its intake by infants.

Polybrominated diphenyl ethers, polychlorinated biphenyls and organochlorine pesticides in human milk as markers of environmental exposure to these compounds

This study aimed at the generation of preliminary results allowing for the assessment of breastfed infants exposure to polybrominated diphenyl ethers (PBDEs) which constitute important contaminants in places of human habitation. The second goal was to compare the concentrations of these compounds with other contaminants which people are exposed to via food chain. 28 breast milk samples from women living in Warsaw and neighbourhood were analyzed for polybrominated diphenyl ethers (BDE-47, BDE-99, BDE-153), polychlorinated biphenyls (CB-77, CB-101, CB-118, CB-126, CB- 138, CB-153, CB170, CB-180) and organochlorine pesticides (HCB, β-HCH, γ-HCH, p,p'-DDE, p,p'-DDD, p,p'-DDT). The ΣDDT levels noted in our studies were higher than in other European countries. The concentrations of the examined polychlorinated biphenyls and polybrominated diphenyl ethers did not diverge from the levels presented by other authors and are comparable to the levels noted in other countries in Europe.

[Application of the quechers method coupled with gas chromatography with electron capture detection (GC-ECD) in analysis of pesticide residues in food]

In 2003 Anastassiades and Lehotay described the "quick, easy, cheap, effective, rugged and safe" (QuEChERS) method for the multi-class, multiresidue analysis of pesticides in fruit and vegetables. The QuEChERS method allows to obtain high quality results with a minimum number of steps and a low solvent and glassware consumption. The QuEChERS method based on liquid-liquid partitioning with acetonitrile followed by a cleanup step with dispersive-SPE (Solid Phase Extraction). The aim of this study was to check the usefulness of the QuEChERS method coupled with gas chromatography with electron capture detection (GC-ECD) in analysis of pesticide residues in food. Ready-to-use QuEChERS reagents kits and own-weighed reagents have been applied. In recovery experiment for 15 selected pesticides, three matrices belonging to different groups--carrots (high carotenoids content), raspberry (highly acidic matrix) and tomatoes (high water content)--have been used, according to the SANC0/10684/2009 guideline and PN-EN 15662:2008 requirements. Fourteen compounds showed a recovery in the range of 70-120% and only one compound (trifluralin in raspberry) presented a recovery lower than 70% at the 0.5 mg/kg fortification level. The repeatability was satisfying with a RSD lower than 20% apart from trifluralin in raspberry (27.16%).

[Dioxins and food safety]

Among numerous potential chemical food contaminants, polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls, collectively referred as dioxins, are commonly considered as bearing substantial risk for human health due to their toxicological properties, persistency and ability to bioaccumulate in food chains. The results of epidemiological studies suggest that environmental exposure to these compounds may affect multiple physiological processes in humans, mainly by the mechanism of endocrine disruption. Adverse health effects linked to the long-term exposure to dioxins include the increase of cancer risk, reproductive and developmental impairment as well as effects on immune functions. Exposure through food (mainly of animal origin) is the major source of dioxin exposure for humans, estimated to account for about 95% of the total intake for non-occupationally exposed persons. Recent studies showed that a consistent part of the European population has an intake exceeding internationally agreed "safe" doses as the Tolerable Daily or Weekly Intake (TDI, TWI). It is worthy to note that percentage of persons with estimated dioxin intake above tolerable limits is much higher among children than in adults. Since the "Belgian dioxin crisis" that occurred in 1999, the estimation of human exposure to these compounds and related consumer risk assessment has been recognized in the European Union as one of the priority activities in the field of food safety. Among activities undertaken by the European Commission during implementation of the Community Strategy for dioxins, furans and polychlorinated biphenyls the maximum and action levels have been established with random monitoring by Member States. The legislation on the requirements for sampling and methods of analysis used in the official control laboratories has been set up as well. Member States are obliged to measure background levels of dioxins and dioxin-like PCBs in defined food categories for the EU monitoring program on a yearly basis and to forward the results to the European Commission (since 2008 to the European Food Safety Authority). The monitoring results, covering samples collected from 1999 to 2008, evaluated and reported recently by EFSA, became the basis for updating maximum levels of dioxins and dl-PCBs as set up in Commission Regulation (EC) 1881/2006. The legislation will also be changed by replacing the current toxicity equivalency factors (TEFs) system from 1998 (WHO,1998-TEFs) by a new TEFs proposed by the WHO in 2005 (WHO 2005-TEFs). It is expected that new limits for dioxins and dl-PCBs in food will come into force not later than in the beginning of 2012.

[Ubiquitous perfluorinated compounds]

Perfluorinated compounds are derivatives of hydrocarbons, in which all or most of hydrogen atoms are substitiuted by fluorine atoms. These compounds are commonly used in many branches of industry. Perfluorinated compounds are in the limelight because of numerous reports concerning their toxicity and negative effects on human health as well as contradictory information about their cancerogenic effect. The above compounds are used in production of many commonly used products including such brand names as Gore-Tex, Teflon, Stainmaster. The most common ways of penetrating these compounds into a human organism are: via food, inhalation and skin contact. Perfluorooctanesulfonate (PFOS) has been added to the list of persistent organic pollutants (POPs).

[Organohalogen compounds--new and old hazards for people]

The organohalogen compounds (OCs, PCBs, PBDEs) are persistent organic pollutants (POPs) that have a widespread distribution in the environment. Their chemico-physical stability and lipophylic properties are responsible for their accumulation in the human body. The general human population is exposed to PCBs and OCs through foodstuffs, mainly food of animal origin. However the main source of the human exposure to PBDEs are also food and inhalation of dust or respirable phase of the indoor air The POPs from this group are present on different levels in human tissues (fat tissue, liver; placenta), and even in human blood and breast milk. The organohalogen compounds may cause endocrine disrupting (ED) effects as they have been shown to interact as antagonists or agonists with androgen, progesterone, and estrogen receptors. Most of them shows antiandrogenic, estrogenic and antiestrogenic activity.

[The role and tasks of the National Reference Laboratory in the scope of pesticide residues in food]

The Member States are obliged to establish the specific programmes and the control systems ensuring that food products placed on the market are safe for the consumer In Poland, the official food control laboratories of the State Sanitary Inspection carry out the analysis of food contaminants, including pesticide residues. Those laboratories closely cooperate with the National Reference Laboratories (NRLs). They are also receiving necessary technical assistance from NRLs.

[Analysis of scientific background of establishing definitions for Maximum Residue Levels (MRLs)]

For each pesticide used in food or feed productions, the legislative authorities have to establish the residue definitions, that mean compounds which need to be taken into account in risk assessment in process of authorization of plant protection products as well as in establishing and enforcing Maximum Residue Levels (MRLs). The residue definition for a given pesticide can be different depending on the aim for which they are used. Inclusion of a compound in such definition results in consequence in its later analysis in different matrices during monitoring and official control. Inclusion of compounds in the definition depends on a number of factors, and the decisions on whether they should be included have to be made for every case separately. The definition should include toxicologically important compounds, and those which contribute into the residue in 10 or more percent of TRR, or those that have been detected in livestock and plants as metabolites different than those found in rats.

[The survey of pesticide residues in food of plant origin in Poland, 2004-2007]

The Member States of the European Union are obliged to provide the official food control. For the pesticides, each country develops the monitoring and official control of pesticide residues in food on the market. In Poland, as in the other Member States, the monitoring of pesticide residues in food and official control are performed in order to check compliance with the Maximum Residue Levels (MRLs). In 2004-2007 the total number of samples analyzed in monitoring and official control of pesticide residues in foodstuffs of plant origin in Poland was 5340. Those were 1419 samples of fruit, 2383 samples of vegetables, 561 samples of cereal crops, 371 samples of processed products, and 509 samples of baby food During those four years residues above the MRLs were detected in 116 samples. The number of exceedances of MRLs was higher in domestic food products, which equaled 90% of analyzed samples.

[Nanotechnology--possibilities and hazards]

Nanoparticles are the objects with at least one demension smaller than 100 nm. Nanoparticles exist in nature or can be produced by human activities, intentionally or unintentionally. Nanotechnology is an emerging science involving manipulation of matter at nanometer scale. Nanoparticles find numerous applications in many fields, starting with electronics, throught medicine, cosmetology, and ending with automotive industry and construction industry. Depending on the use of nanoparticles, the routes of exposure may be inhalation, dermal, oral or parenteral. Nanoparticles have a greater active surface area per unit mass than larger particles. Together with an increase of surface area, toxicity and potential health effects may also increase. Toxicity of nanoparticles depend on many factors, for example: size, shape, chemical composition, solubility, surface area and surface charge. Risk assessment related to human health, should be integrated at all stages of the life cycle of the nanotechnology, starting at the point of conception and including research and development, manufacturing, distribution, use and disposal or recycling.

[The application of statistical methods in chemical experiments]

Quality of the analyzed data has a major impact on reliability of the results. Application of statistical methods allows to reduce some stages of chemist's work, for example classification of the numerous data sets. The statistical methods are applied for preliminary evaluation of the data quality. In this case it is necessary to verify that the raw data base does not include large errors or outliers, which could influence the result of experiment. Data analysis, which is performed by chemometric techniques, rely on finding the most correlated attributes. Chemometry is used towards creation of the mathematical model of relation between analyzed property and numerous sets of described variables (parameters which affect measure). Modeling requires calculations towards model identification, checking its relevance, evaluation of the adequacy and determination of model's prognostic ability. The obtained model of relation could be used for the system optimization in the technological process, forecasting the values subsidiary conditioned upon known values described, also for control of the analytical system. The statistical methods are applied in chemical studies for data collection and analysis of chemical compounds for more efficient management of flow of the information. They allow to foreseen physical and biological properties of chemical compounds. The statistical methods are also applied for quality management in chemical analysis of contaminants including pesticide residues in foodstuff.

[Consumer risk assessment in case of maximum residue levels (MRLs) violations in food]

Maximum Residue Levels (MRLs), as legally binding normative values, have appeared in Polish food legislation for the first time in 1993. Currently, existing MRLs include those values implemented from EU Directives and National MRLs set up by experts from the National Institute of Hygiene. Monitoring of pesticide residues allows to assess exposure of consumers to these compounds present in food products. Monitoring results can also influence the scope of plant protection products application, and change in MRLs. Another tool used to check compliance of food products with MRLs is official control of foodstuffs. Poland, since its accession to the European Union in 2004 takes part in the EU coordinated monitoring programme and carries out the official control of pesticide residues in foodstuffs. Food present on the market must not contain pesticide residues at level exceeding legally binding MRLs. Each case of MRLs violation requires performing of individual risk assessment. In such case so called Predicted Short Term Intake from sampling result (PSTI) is calculated and compared to ARfD or to ADI. Such an assessment is applied to a high percentile of consumption (97,5) among general population (adults) and among the most vulnerable consumer group (children aged 1,5 up to 6 years old). Depending on the results of the assessment, the information about MRL exceedances may be notified to the Rapid Alert System for Food and Feed (RASFF) by the Polish Contact Point placed in Chief Sanitary Inspectorate. In Poland, the risk assessment for MRLs violations is performed in the National Institute of Hygiene. The result of risk assessment is a basis for Chief Sanitary Inspector to undertake appropriate risk management decisions to eliminate of potential health risk for consumers.

[Polybrominated diphenyl ethers (PBDE)--new threats?]

Polybrominated diphenyl ethers (PBDE) because of their physical and chemical properties belong to Persistent Organic Pollutants (POPs). They are stable in the environment and due to lipophilic properties, have potential impact to human health. Currently these compounds are present in all kind of environmental samples all over the world. Levels of PBDE in samples originated from U.S. are higher than levels reported from Europe and Japan, what may be linked to common use these flame retardants in this country. Environmental (including humans) concentration of PBDE have increased rapidly in the last decade. Predominant congeners detected in all matrices are BDE-47, -99, -153, -209. Recent Swedish report however noticed decrease of PBDE concentrations what can be consequence of phase-out of these compounds in this country. It has been suggested that the environmental levels of PBDE may influence human nervous and immunological system as well as they may disrupt hormonal homeostasis. Research studies suggest also that the exposure to polybrominated diphenyl ethers may be associated with increased risk of cancers. Therefore, continuation of research concerning occurrence and toxicity of PBDE has reasonable grounds.

[Dietary risk assessment for pesticide residues in food of plant origin during the plant protection product's registration process]

One of the main goals of risk assessment during registration of plant protection product is to approve (or not) the proposed Maximum Residue Levels (MRLs) derived from the field trials conducted under Good Agricultural Practice (GAP). Generally, risk assessment at this stage is based on comparison of potential long- and short-term dietary intake of given pesticide with two earlier established outputs of hazard characterisation, i.e. Acceptable Daily Intake - ADI and Acute Reference Dose--ARfD. The first estimate of long-term hazard, which overestimates the risk, is comparing the Theoretical Maximum Daily Intake (TMDI) to the ADI of the pesticide. TMDI is based on assumption that all food products consumed over the lifetime of the consumer contain residues at level of MRL. Afterwards, the ADI is compared against International/National Estimated Daily Intake (IEDI/NEDI). I(N)EDI values provide a "best estimate" of dietary intake as they take into account residues in edible portions at level of median residue values from supervised trials. In case of short-term dietary exposure to acute toxic pesticides, the intake is compared to ARfD. The calculation of International/National Estimated Short-Term Intake IESTI/NESTI) requires single-day consumption data for the 97.5th percentile for each subgroups of consumers (so called "large portions") together with typical unit weight, and percentage of edible portion for each commodity as well as high, and median residue levels derived from the field trials. Additionally, in intake calculations for commodities with unit weight over 25 g, the variability factor (from 3 to 10) has been introduced, which reflects the possible high deposition of a pesticide on the individual unit, even when the quantified residue level in composite sample is relatively low.

[Levels of selected organochlorine insecticides, polychlorinated biphenyls, phthalates and perfluorinated aliphatic substances in blood--Polish WWF study]

In June 2004, blood samples of fifteen volunteers were analyzed for presence of selected groups of chemical contaminants. The aim of this survey organized by WWF Poland (World Wildlife Fund) was highlighting the problem of man-made, persistent and bioaccumulative chemicals constantly present in surrounding environment and in our tissues. It was a part of European WWF "Detox" campaign supporting proposal of a new EU regulation that should lead to the identification and phasing out of the most harmful chemicals (known as REACH). Three laboratories in Czech Republic, Sweden and Belgium have analyzed blood samples for presence of the following groups of contaminants: organochlorine compounds (pesticides and polychlorinated pesticides), phthalates and perfluorinated aliphatic substances. The total number of single chemicals found in the blood samples was 25, that represents 64% of the 39 chemicals looked for. The average number of compounds found in the samples was 21 (from 19 to 22). Among organochlorine compounds analyzed, the predominant chemical found in the highest concentration was p,p'-DDE (range from 130 to 1310 ng/g of fat), which similarly like p,p'-DDT, beta-HCH, and HCB (concentrations ranging from 6,4 to 46 ng/g of fat) was present in every person's blood. Among analyzed polychlorinated biphenyls, in all samples the following congeners have been present: PCB-118, PCB-138, PCB-153, and PCB-180 (concentrations ranging from 3,7 to 61 ng/g of fat). The two predominant phtalates from total eight analyzed present in all samples were di(2-ethylhexyl)phthalate (DEHP) (concentration range from 49 to 293 ng/g of blood) and diisobutyl phthalate (DIBP) (concentration range from 10 to 63 ng/g of blood). Among fifteen perfluorinated aliphatic substances analyzed, six have been present in each single sample (perfluorohexanesulfonic acid - PFHxS, perfluorooctanoic acid - PFOA, perfluorooctane-sulfonic acid - PFOS, perfluorooctanesulfonylamide - PFOSA, perfluorononanoic acid - PFNA, and perfluorododecanoic acid - PFDA). The predominant compound in this class of contaminants was PFOS with the concentration ranging from 4,4 to 14 ng/ml of blood. The limited number of samples does not allow for making an analysis of potential impact of different factors on concentrations of particular contaminants in human blood. Results obtained in this survey confirm the ubiquitous contamination by a cocktail of hazardous chemicals of every person tested. Humans being a part of the environment are being contaminated with the same chemicals which are present in surrounding air, water, food, consumer articles, etc.

[Evaluation of the usefulness of SIS and MS/MS mode for the determination of persistent organochlorine compounds and polychlorinated biphenyls in human specimens]

This study aimed of examining of the applicability of the SIS (Selected Ion Storage) and the MS/ MS (Tandem Mass Spectrometry) methods for analyzing organochlorine pesticide (OCs) residues and PCBs in human specimens. The samples of human abdominal adipose tissue, women's breast adipose tissue, and human milk were used as study material. The samples were analyzed using the gas chromatography method with EC and MS detectors. MS/MS and SIS mode allow to eliminate system-based (e.g., column, septum) ions and the biological samples extract impurities' ions from the background to achieve the analytical system sensitive enough for trace analysis of organochlorine compounds in human specimens.

[Monitoring and official control of pesticide residues in foodstuffs in Poland in 2004]

Poland, as a Member State of the European Union, is obliged to establish efficient system of food control allowing assessment of health quality of food products for general population as well as for high risk groups, like infants and toddlers. In case of pesticide residues this task is realized by carrying out programs of monitoring and official control of foodstuffs in order to check compliance with Maximum Residue Levels set up by Polish Regulation of Minister of Health on maximum residue levels of pesticides in or on food. The Chief Sanitary Inspectorate is an authority responsible for above mentioned activities with essential participation of Department of Environmental Toxicology of National Institute of Hygiene. The analysis of food samples indicated in yearly developed plans of sampling, is carried out in 16 integrated local laboratories of National Sanitary Inspection. In 2004, 868 samples have been analyzed in system of monitoring and official control of foodstuffs in Poland. The samples were taken in retail and wholesale. Among analyzed samples 67% were fresh or frozen fruit and vegetables, and 14% were baby food. The samples have been analyzed or presence of over 50 pesticides. In the year 2004 maximum residue levels have been exceeded in 14 samples (2%) of fruit, vegetables and cereals. All samples were of Polish origin, except two samples from Spain. In samples with violated MRLs the following pesticides have been found: Benomyl group, Maneb group, Endosulfan, Mecarbam, Hexachlorobenzene, and Methyl bromide. Additionally, 49 follow-up enforcement samples has been analyzed. In none of them MRLs violation have been found.

[Health hazard for medical staff exposed to nitrous oxide]

The paper briefly reviews available data on occupational exposure to nitrous oxide and health consequences in medical staff. Special attention is paid on causes of nitrous oxide contamination in occupational environment and monitoring its concentrations. On the basis of the epidemiological studies it was ascertained that nitrous oxide exerts multiple deleterious effects on human organism, especially on fertility, pregnancy, central nervous system and bone marrow.

[Validation methods and ambiguous results in the analysis of pesticide residues in food]

Laboratories routinely analyzing pesticide residues in food should apply analytical methods fulfilling criteria specified by international institutions and published by World Health Organization, Food and Agriculture Organization, and European Union. Additionally, these methods should be validated by particular laboratory, and the uncertainty of obtained results should be assessed. When the client requires, the laboratory should present the results in the report with extended uncertainty.

[The role of nuclear receptors in cytochrome P-450 induction by xenochemicals]

This review summarizes recent findings indicating that members of the orphan nuclear receptor superfamily regulate the synthesis of their CYP genes which code CYP enzymes involved in metabolism of endogenous and exogenous compounds. The foreign compounds metabolism and the role played by individual cytochrome P450 (CYP) enzymes in the activation and detoxification of xenochemicals prevalent in the environment are important areas of molecular pharmacology and toxicology. The advances in our understanding of the mechanisms through which foreign chemicals impact on these CYP-dependent metabolic processes have been made during the past years. Role for three "orphan" nuclear receptor superfamily members, designated CAR (constitutive androstane receptor), PXR/SXR (pregnelone X receptor) and PPAR (peroxisome proliferator activated receptor), in respectively mediating the induction of hepatic CYPs belonging to families CYP2, CYP3, and CYP4 has now been established. The CYP gene products such as CYP3A, CYP2B and PPAR are essential for metabolism of endogenous steroid hormones, fatty acids and various xenobiotics including drugs. Unexpectedly, it has been shown that SXR, which regulates CYP3A, can also regulate CYP2B via recognition of the phenobarbital response element (PBRE). In a type of functionally symmetry, orphan receptor CAR was found to activate CYP3A through SXR/PXR response element. Indeed, SXR/PXR binds to inverted (IR-6) and direct (DR-4) response element localized to regulatory DNA regions of human CYP3A4 and rat CYP3A23 genes, respectively. These observations provide a rational explanation for the activation of multiple CYP gene classes by certain xenobiotics as well as the propensity for drug-drug interactions. In addition, both endogenous and exogenous ligands which act as activators of nuclear receptors can result in disruption of cellular homeostasis.

[Levels of organochlorine insecticides in Polish women's breast adipose tissue, in years 1997-2001]

Although manufacture and use of chlorinated insecticides was banned or severely restricted in most of countries in the 1970s, the residues of these compounds are still detected in various environmental matrices all over the world. Their highest levels are found in adipose tissue of beings at the top of food chain, including humans. Levels of persistent organochlorine compounds in human specimens are monitored by numerous scientific organizations in various countries, including Poland. The purpose of the study was to survey the current levels of selected organochlorine insecticides (isomers alpha-, beta-, gamma-, delta-HCH, o,p'- and p,p'-DDT, DDE i DDE, oxy-chlordane and heptachlor) in women's breast adipose tissue which can be an indicator of body burden. A total of 67 samples of adipose breast tissue collected between 1997 and 2001 from non-cancer patients, aged from 15 to 74 years have been analyzed. The analytical procedure included extraction, clean-up and analysis by means of GC-ECD with GC-MS confirmation. In all the samples analyzed p,p'-DDE, p,p'-DDT and beta-HCH were present (mean values, expressed as mg/kg of fat: 0.7700, 0.0720, and 0.0635 respectively) with p,p'-DDE, found to be dominant analyte. The levels of the remaining compounds, were usually about or below the method quantification limits (from 0.0025 to 0.0060 mg/kg of fat). The results for DDTs and beta-HCH for the oldest group (above 50 years) were 2.1 to 3.6 times higher than the youngest group (below 39 years). The results obtained in this study are similar to those reported in analogous samples collected from women living in other European countries with similar climate and history or organochlorines usage as well as in the USA. The presence of some organo-chlorine insecticide residues in women's adipose tissue, even those, who were born even 10-15 years after most countries introduced severe restrictions or banned the use of these compounds may be cause for anxiety. That is due to the potential of these compounds to promote toxic effects, including disrupting the human endocrine system.

[Flame retardants--use and hazards for human]

Flame retardants (FRs) are chemicals which added to materials during or after manufacture, inhibit or even suppress the combustion process due to their thermal stability. Large quantities of FRs are added to the plastic material (resins) in variety of electrical and electronic appliances including television and computer casing. The other uses of these compounds include production of building materials, upholstered furniture, textiles, wall covering, carpets, hydraulic fluids as well as vehicles and aircraft. Taking into account the chemical structure, there are five main groups of FRs: brominated, chlorinated, phosphorous-containing, nitrogen-containing (i.e. melamines) and inorganic compounds. Halogenated compounds, especially polybrominated diphenyl ethers (PBDEs), a class of brominated flame retardants, due to their lipophilic characteristics and persistence have become ubiquitous environmental contaminants. There are indications that PBDEs may affect hormone function acting as endocrine disruption and may be toxic for developing brain. These compounds have been associated with non-Hodgkin's lymphoma in humans, a variety of cancers in rodents and disruption of thyroid hormones balance. Similarly to other persistent halogenated compounds they are also able to affect the xenobiotic metabolizing enzymes activity. PBDEs are now found as residues in sediments, wildlife and human (milk, serum adipose tissue) samples. The predominant congeners in environmental samples, including human specimens are two congeners: 47 and 99. Currently, the estimated daily intake of PBDEs by adult humans is equal 51 ng x day-1 while by breast-fed infants equals 110 ng x day-1.

[High performance liquid chromatography: application in pesticide residue analysis]

Chromatographic techniques allow separation and quantitation of trace levels of organic compounds in different matrices. Chromatography is widely used in many scientific areas, including food safety. Currently, high performance liquid chromatography (HPLC) and related techniques have become the dominant analytical separation tools in such areas as pharmaceutical, chemical and food industries and environmental monitoring. Contrary to gas chromatography (GC), HPLC allows to determine low-volatile and thermolabile compounds. A variety of packings and bonded phases as well as eluents and their combinations make this technique very useful in analysis of food contaminants, including pesticide residues. Plant protection products, called commonly pesticides, contain biologically active substances having wide mode of action, used in crop protection and in many other areas. Unfortunately, besides advantages related to their use, it should be taken into account that they are also toxic for humans and environment. As general population is exposed to pesticides mainly through the food, it is necessary to monitor concentrations of these compounds using sensitive techniques for ppm or even ppb levels. This article discusses the advantages of HPLC technique for the residues analysis of some active substances of plant protection products.

Relationship between two consecutive lactations and fat level in persistent organochlorine compound concentrations in human breast milk

An attempt was made to understand how consecutive deliveries and the following lactations have an impact on the organochlorine compound levels detected in human milk. The other goal of the study was to check for a possible dependence between fat content and the levels of the studied compounds in milk samples from the same lactations. 199 milk samples were examined for the presence of p,p'-DDT, p,p'-DDE, p,p'-DDD, alpha-, beta-, gamma-HCH and sigmaPCBs. Moreover, in 87 milk samples the fat content was additionally determined. This study has indicated that, for the mother with a shorter interval between lactations, mean concentrations of the examined compounds were higher in the milk of the first lactation than that of the second. For the other donor whose second lactation began after 2 years, the mean levels of HCB, beta-HCH, p,p'-DDD, and PCBs in her milk were higher during the first lactation. At the same time, the concentrations of p,p'-DDT and p,p'-DDE after the second delivery were slightly higher. The correlation coefficients between the two data sets (fat content in milk, concentrations of the compounds studied in milk) showed no interrelationship between them.

[Selected aspects of xenoestrogens'mode of action taken from a group of persistent organochlorine compounds ]

The presence of many chemical pollutants in the environment and their potential impact to human health creates rather justified anxiety. Many of these pollutants feature such unwelcome characteristics as: persistence in different environmental media, ability to bioaccumulate and biomagnify in individual food chains, as well as ability to undergo long-range atmospheric transport. Compounds meeting these criteria include above all a large group of persistent organochlorine compounds. Recently, debate has increased concerning endocrine disrupting activity of these compounds and especially their ability to produce biologic responses comparable to those of endogenous estrogens (e.g., 17 beta-estradiol). It has been hypothesized that these compounds, among others, may be associated with increased incidence of breast cancer and other estrogen-related cancers in women due to increased proliferation of breast epithelial cells. The organochlorine xenoestrogens may produce this effect following binding to a hormone receptor (with or without metabolic activation) or by affecting the 17 beta-estradiol pathways leading to increased formation of more potent estrogenic metabolites. Numerous studies performed since early 1990s have examined the relationship between organochlorines levels in serum or adipose tissue and breast cancer, but the results are not consistent. This may be caused by various criteria of selecting the case and control groups, different compounds analyzed or different statistical approaches. None of these studies included endocrine disruptors' exposure in early and critical stages of development--from conception up to puberty age--the results of which would manifest in far future. Nevertheless the results of measurements, especially in adipose tissue are more reliable for this purpose because they reflect the whole life exposure and may be recognized as one of many environmental risk factors of cancer development.

[Levels of organochlorine insecticides in citrus fruits in 1996-1997]

The monitoring of organochlorine insecticides (HCB, HCH, and DDT) in citrus fruits taken from the market was carried out in 9 regions in Poland in the years 1996-1997. The concentrations of the insecticides were measured in the edible part and in the peel separately. The total number of 331 samples of oranges, lemons, grapefruits and mandarins were subjected residue analysis. The mean concentrations of the organochlorine compounds in the edible parts amounted 0.0002 mg/kg for HCB, and ranged from 0.0081 to 0.0247 mg/kg for sigma HCH and from 0.0041 to 0.022 for DDT depending on the product. The highest contrentrations together with the highest violation rate (9.5%) of the Polish Maximum Residue Limit was found in case of DDT. The mean concentrations of the insecticides in the citrus peels were not markedly higher than those in the edible parts. The results obtained in this monitoring did not differ from the results reported by the other authors.

Effect of changes in excretion of persistent organochlorine compounds with human breast milk on related exposure of breast-fed infants

This study was an attempt to identify if there are any trends in excretion of 1,2,3,4,5,6-hexachlorocyclohexane (HCH) isomers alpha-, beta-, and gamma-, hexachlorobenzene (HCB), [1,1,1-trichloro-2, 2-bis(4-chlorophenyl)ethane] (p,p'-DDT), [1,1-dichloro-2, 2-bis(4-chlorophenyl)ethane] (p,p'-DDD), [1,1-dichloro-2, 2-bis(4-chlorophenyl)ethylene] (p,p'-DDE), and polychlorinated biphenyls (PCBs) with human milk during lactation. The shortest lactation studied took 16 weeks, and the longest 84 weeks. Three hundred fifty-two milk samples, collected from each donor once a week, were examined. The analysis of the result showed individual differences in the excretion of the compounds. The findings from this study are not conclusive enough to claim that there are consistent trends showing a decrease or increase in the excretion of the compounds under examination. Thus, one cannot claim that the infants' exposure to those compounds decreases or increases as breast-feeding continues.

[Monitoring of pesticides residues in food in Poland]

In this paper, the results of monitoring of pesticide residues in food products are reported for the 3 years period 1995-1997. The monitoring included analysis of organochlorine compounds (DDT and its metabolites--DDD and DDE, HCH isomers alpha, beta and gamma, HCB and PCBs), pyrethroids and dithiocarbamates in variety of food products such as: milk and milk products, food for infants and children, fish products, potatoes, domestic fruit and vegetables, citrus and exotic fruits, which were taken from the market. The samples were collected from 15 regions of Poland. Mean values of sigma DDT and sigma HCH in food products of animal origin, including children foods, were much lower comparing with those, reported in previous years. Only few samples analyzed had violative residues exceeding Maximum Residue Limits (MRLs) for these compounds. In none of food samples of plant origin, organochlorine compounds residues exceed Polish tolerances. The residues of synthetic pyrethroids were detected in none of tested samples of potatoes. Mean concentrations of dithiocarbamate pesticides in fruit and vegetables were higher than observed at the beginning of 1990s. In five samples of leaf and stem vegetables, the detected levels of dithiocarbamates exceed or were equal to MRLs.