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Pesticides in precipitation in the Gdańsk region (Poland).

Selected organonitrogen, organophosphorus and organochlorine pesticides have been determined in precipitation samples collected at 10 sites in the Gdańsk region (northern Poland) over a period of one year (1998). Compounds which were detected most often included simazine (0.11-5.80 ng/l), fenitrothion (0.1-2.10 ng/l), chlorfenvinfos (0.1-1.30 ng/l), gamma-HCH (0.012-5.06 ng/l), heptachlor epoxide (0.05-3.28 ng/l) and aldrin (0.02-3.28 ng/l). The pesticide concentrations in precipitation samples revealed seasonal fluctuations, with higher concentrations observed during the application periods (June and July). The concentrations observed were also affected by the inflow of polluted air masses from the southwest. The total pesticide concentration in the precipitation samples was strongly related to the abundance of green areas in the vicinity of the sampling sites. A weak correlation was also found between the total concentration of organonitrogen and organophosphorus pesticides, and the total concentration of organochlorine pesticides in the samples collected.

Air Pollutants↗

Adsorption/thermal desorption-GC/MS for the analysis of pesticides in the atmosphere.

An analytical methodology using Automatic Thermal Desorption (ATD) and GC/MS was developed for the determination of the pesticides alachlor, atrazine, captan, formothion, lindane and phosalone in atmospheric samples. This methodology was developed to evaluate the atmospheric contamination by pesticides during treatments and by post-application. Atmospheric samples were collected by using (4 i.d. x 89 mm) stainless steel sampling tubes containing 125 mg of adsorbents at a flow rate of 80 ml min-1. Different types of adsorbents were tested for their ability to efficiently trap pesticides under study: Tenax TA, Carbopack Y, Carbopack B, Carbotrap, Carboxen, Chromosorb 106 and XAD-4. Results of experiment show that Tenax gives the better results for all the pesticides used but the use of the thermal-desorption method, especially for pesticides with low volatility and/or poor thermal stability presents some difficulties. This method was validated by the analysis of the contamination of atmosphere, through volatilization by post-application processes, of atrazine in a parcel of 1 ha.

Acetamides↗

Assessment of organochlorine pesticide residue levels in dairy milk and buffalo milk from Jaipur City, Rajasthan, India.

The widespread application of pesticides in agriculture, public health, and industry and in and around the home can result in the accumulation of pesticides in the environment. Therefore, a survey has been conducted during 1993-1996 to investigate the magnitude of contamination of bovine milk with organochlorine pesticide (OCP) residues from Jaipur City, Rajasthan, India. Milk samples, i.e., dairy (toned and whole) and buffalo milk, were collected seasonally, and pesticide residues were assessed using a gas chromatograph (GC) with an electron capture detector (ECD). The results indicate that all the milk samples were contaminated with dichlorodiphenyltrichloroethane (DDT) and its metabolites (DDE and p,p'-dichlorodiphenyldichloroethane [DDD]), isomers of hexachlorocyclohexane (HCH; alpha, beta, and gamma), heptachlor and its epoxide, and aldrin. Seasonal variations of these pesticide residue levels were also observed in all the milk samples. Samples collected during winter season were found to contain higher residue levels as compared to other seasons.

Animals↗

The contamination with organochlorine pesticides and heavy metals in surface water in Küçük Menderes River in Turkey, 2000-2002.

This study was conducted from 2000 to 2002 to determine the residues of organochlorine pesticides (OCP) and metals in surface water of Küçük Menderes River in Turkey. The results showed that Küçük Menderes River was still polluted with organochlorine pesticide despite the existence of bans over a long time. The concentrations of pesticides depended on the sampling season and the tendency was not the same for all detected pesticides. The DDTs (DDT, DDD, DDE) were detected in most water samples. DDD showed a high concentration among DDTs. The highest concentration among organochlorine pesticides was heptachlor epoxide by 281 ng/l. However, the residues were lower than most polluted water from other sources in the world. In most cases, they were not detectable. The studied surface water metals varied from not detected to 0.258 mg/l, and the residues were low except for Ni, Cu, and Zn.

Environmental Monitoring↗

Pesticide effects on freshwater zooplankton: an ecological perspective.

The effects of pesticides on zooplankton are reviewed and their ecological significance is discussed. Toxicity is shown to vary depending on animal species, genotype, life stage, and size at birth. Natural stresses such as food shortage, oxygen depletion and odors of potential predators can also affect toxicity. Populations in the growth phase are vulnerable to pesticides but have the potential to recover rapidly from the damage. Pesticides may affect the population dynamics by controlling individual survival and reproduction, and by altering the sex ratio. Furthermore, toxic chemicals may control predation risk by changing swimming behavior and body morphology, and this in turn influences the population dynamics. Many zooplankton display morphological and behavioral responses to predators when exposed to their odor-producing chemicals. However, pesticides induce a maladaptive response to predator odor, and this poses an ecological risk. The following patterns are recognized as effects of pesticides at the community and ecosystem levels: (1) induction of dominance by small species; (2) an increase of species richness and diversity; and (3) elongation of the food chain and reduction of energy transfer efficiency from primary producers to top predators.

Animals↗

Changes in concentration of pesticide residues in potatoes during washing and home preparation.

Monitoring of pesticide residues in potato tubers and their prepared products ("pommes frites" and chips) was undertaken. Experiments were carried out to determine changes in concentration due to the washing, peeling and cooking process (blanching and frying) to assess the stability of pesticides in potatoes and their products. Pesticide residues were quantified by using gas chromatography. Results show that malathion, HCB, lindane and p,p-DDD were predominant in potatoes and their products. The highest mean was detected in potatoes, followed by pommes frites, while the lowest mean was recorded in chips. On the other hand, potato skin samples were found to contain the highest levels of DDT and its derivatives, lindane and HCB. Peeling was necessary to remove the greatest amount of pesticides in the skin. Washing with water and/or other solutions as well as the cooking process (blanching and frying) helped to eliminate most of the pesticide residues from the potato tubers.

Chromatography, Gas↗

Estimation of risks of pesticide exposure, by food intake, to Koreans.

The aim of this study was to evaluate theoretical maximum daily intake (TMDI) and estimated daily intake (EDI) for Korean by using maximum residue levels (MRLs), food intake, residue data and correction factors, and compare with acceptable daily intake (ADI) in order to estimate the health risk based on the pesticide exposure. Then, the oncogenic risks of the pesticides were assessed from TMDI and estimated daily intake with treatment (adjusted EDI). The percent ratio of TMDI to ADI for 262 pesticides was mostly below 80%, but 42 pesticides (16.0%) exceeded the ADI. EDI without treatment (non-adjusted EDI) and estimated daily intake with treatment (adjusted EDI) were summed up to about 6.41 ml/day/capita and 2.94 ml/day/capita, respectively. The percentage of ADI was TMDI (101.04%) > non-adjusted EDI (0.08%) > adjusted EDI (0.01%), and the exposure level of Korean population to whole pesticides was below the level to produce health risk. The dietary oncogenic risk for Koreans was estimated to be 7.3x10(-4) on the basis of TMDI, 1.8x10(-7) on the basis of adjusted EDI, and although the level from TMDI exceeded the risk level (1x10(-6)) of the Environment Protection Agency (EPA), the level from adjusted EDI, real exposure level, was below it.

Eating↗

Determination of the immunotoxic potential of pesticides on functional activity of sheep leukocytes in vitro.

The effect of eight pesticides with different chemical structure (atrazine, bentazone, chloridazone, dichlofluanid, endosulfan, MCPA, simazine, triallate) on sheep peripheral blood phagocytes and lymphocytes was examined under in vitro conditions by iodo-nitro-tetrazolium reductase test and leukocyte migration-inhibition assay. The pesticides, dissolved in DMSO, were tested at the concentrations of 10(-1)-10(-6) M. The significant suppression of metabolic activity of phagocytic cells was registered after exposure to dichlofluanid (10(-1)-10(-3) M), endosulfan, simazine and triallate (10(-1) M). The significant cytotoxic effect (the decrease of spontaneous migration of leukocytes) was registered for bentazone, dichlofluanid, endosulfan and MCPA (10(-1) M); chloridazone (10(-1) M-10(-2) M) and triallate (10(-1)-10(-5) M). The significant immunotoxic effect (the decrease of lymphocyte activation with PHA) was observed for atrazine (10(-1)-10(-2) M); bentazone (10(-2)-10(-4) M); dichlofluanid, endosulfan (10(-2)-10(-3) M); MCPA (10(-2)-10(-6) M) and simazine (10(-1)-10(-4) M). Three of the pesticides tested suppressed both, the metabolic activity of phagocytes and mitogenic activation of lymphocytes (dichlofluanid, endosulfan and simazine). Triallate suppressed the metabolic activity of phagocytes and showed a strong cytotoxic effect. Pesticides atrazine, bentazone and MCPA influenced the mitogenic activation of lymphocytes and chloridazone showed a significant cytotoxic effect. The different chemical structure of pesticides influenced the metabolic activity of phagocytic cells as well as mitogenic activation of lymphocytes to various intensity.

Animals↗

Food contamination by metals and pesticides in the European Union. Should we worry?

The estimation of the risk associated with dietary intakes of heavy metals and pesticide residues by the consumer is a vital and integral part of regulatory processes. The exposure of the consumer is compared directly to the acceptable daily intake (ADI) for pesticides and to the tolerable daily intake (TDI) for heavy metals. The exposure is obtained using the basic equation: Exposure (mg/kg b.w./day)=Consumption (mg/kg b.w./day) x Residue (mg/kg). The establishment of the ADI and the TDI is based on the results of toxicological studies that involve the determination of the lowest-no-observed-adverse-effect level/10 (SF1) x10 (SF2), where SF corresponds to 'Safety Factor'. SF1 and SF2 account for interspecies and intraspecies variability, respectively. In order to evaluate the risk for the consumer, that is associated to the presence of heavy metals and pesticides in food, a review of the level of contamination in European countries has been made. The exposure of European consumers to lead, cadmium, arsenic and mercury is superior to the TDI. For pesticides, the first step is to compare the detected amount of residues of a specific pesticide to the maximum residue level (MRL) authorized in foodstuffs. If the residue level in food exceeds the MRL, the theoretical maximum daily intakes and the ADI have to be taken into account in order to assess the risk for the consumer.

Cadmium↗

Environmental risk assessment of pesticides on aquatic life in Xiamen, China.

This paper describes the results of the environmental risk assessment of the pesticides used in agriculture in Xiamen, China. The goal was to assess the impact on water resources, particularly on fisheries and mariculture. Data on ecotoxicological properties of the pesticides and their physico-chemical profile were collected. The simulation of the environmental behaviour of the pesticides in relation to the load applied onto the agricultural areas was done using the SoilFug model. Risk assessment was performed, pesticides approximate concentrations have been calculated, chemicals at highest risk were identified, and risk management measures were indicated. This study could represent a cost-effective method that may be used before engaging in expensive monitoring programs for pesticide use in developing countries, where analytical facilities are lacking.

Animals↗

Immunological parameters in humans exposed to pesticides in the agricultural environment.

Immune parameters were examined in 224 sera of non-exposed controls and in 304 sera of pesticide applicators in the agricultural environment. In comparison to the control group pesticide applicators showed significant increased odds ratios for neopterin and soluble tumor necrosis factor receptor (sTNF RII) and a decreased odds ratio for immunoglobulin M. Obtained results indicate an enhanced macrophage activation and an impaired humoral defense. These alterations have been found to correlate with exposure duration in the group of pesticide applicators in agriculture. For subjects who worked in indoor pest control an inverse correlation for sTNF RII with exposure duration was obtained indicating impairment of cell mediated immune function. It can be concluded that exposure to pesticides in the agricultural environment may contribute to modulation of the immune system. Since immune modulating agents can potentially lead to adverse health consequences the involvement of immune biomarkers in pesticide-related health studies seems to be of considerable value for risk assessment studies.

Antigens, CD↗

Sensitive and specific multiresidue methods for the determination of pesticides of various classes in clinical and forensic toxicology.

Original and sensitive multiresidue methods are presented for the detection and quantitation, in human biological matrices, of 61 pesticides of toxicological significance in human. These methods involved rapid solid-phase extraction using new polymeric support (HLB and MCX) OASIS cartridges. Gas chromatography-mass spectrometry (GC-MS) was used for volatile (organophosphate, organochlorine, phtalimide, uracil) pesticides and liquid chromatography-ionspray-mass spectrometry (LC-MS) for thermolabile and polar pesticides (carbamates, benzimidazoles). Acquisition was performed in the selected ion monitoring (SIM) mode. Extraction recovery varied owing to the nature of pesticides, but was satisfactory for all. Limits of detection (LODs) and limits of quantitation (LOQs) ranged, respectively, from 2.5 to 20 and from 5 to 50ng/ml. An excellent linearity was observed from LOQs up to 1000ng/ml for all the pesticides studied. The proposed procedures yielded reproducible results with good inter-assay accuracy and precision. A few cases of intoxication are presented to demonstrate the diagnostic interest of these methods: in two cases were determined lethal concentrations of endosulfan and carbofuran; in four other cases, the procedures helped diagnose intoxication with, respectively, parathion-ethyl, the association of bromacil and strychnine, bifenthrin and aldicarb.

Adult↗

Multiresidue method for pesticides in drinking water using a graphitized carbon black cartridge extraction and liquid chromatographic analysis.

A general liquid-solid extraction procedure for the isolation of pesticides from groundwater and drinking water for high-performance liquid chromatography (HPLC) is presented. This simple and rapid procedure involved passing a 2-L sample through a 250-mg graphitized carbon black (Carbopack B) cartridge at a flow rate of 150-160 mL/min. By taking advantage of the presence of positively charged active centers on the Carbopack B surface, a stepwise elution system allowed the complete separation of base-neutral pesticides from acidic ones. After partial solvent removal, the components in the two fractions were separated and quantified by gradient elution, reversed-phase HPLC with ultraviolet (UV) detection. The performance of the Carbopack cartridge was compared with that of a 500-mg C-18 bonded silica cartridge. With the Carbopack cartridge, the grand mean measurement accuracy of the 35 pesticides considered was 95%. With the C-18 cartridge, the grand mean measurement accuracy of the analytes was 76%. Compared to the C-18 cartridge, additional advantages of using a Carbopack cartridge are that the extraction procedure is about 7 times shorter, no pH adjustment of the environmental sample is necessary for trapping acidic compounds, and one cartridge instead of two suffices to extract base-neutral and acidic pesticides, making the Carbopack cartridge more adaptable than the C-18 one for field use. The detection limits by this method of all the pesticides considered were between 0.003 and 0.07 micrograms/L.

Carbon↗

Electrochemical detection of carbamate pesticides at conductive diamond electrodes.

Conductive boron-doped diamond thin-film electrodes were used for the electrochemical detection of selected N-methylcarbamate pesticides (carbaryl, carbofuran, methyl 2-benzimidazolecarbamate, bendiocarb) after liquid chromatographic separation. Two kinds of detection methods were adopted in this study. In the first method, a direct detection of underivatized pesticides was carried out at an operating potential of 1.45 V versus Ag/AgCl, which resulted in the detection limits of 5-20 ng/mL (or 5-20 ppb) with S/N = 2 due to the low background current and wide potential window of the diamond electrode. In the second method, the detection limits were improved by subjecting the pesticide samples to alkaline hydrolysis in a separate step prior to injection. The phenolic derivatives obtained by alkaline hydrolysis oxidize at a relatively lower potential (0.9 V vs Ag/AgCl), which increases the sensitivity drastically. The advantage of the diamond electrode for the detection of phenolic derivatives is that it offers excellent stability in comparison to other electrodes. This method gives the detection limits of 0.6-1 ng/mL (or 0.6-1 ppb), which are well below the maximum residue levels allowed for carbaryl, carbofuran, and bendiocarb. While the lowest detection limits (LOD) obtained by the direct detection of pesticides are comparable to the those reported by the well-established HPLC-fluorescence, the LODs of the alkaline hydrolysis method are found to be even lower than the reported limits. On-line reactivation of the diamond electrode surface was shown to be possible by an anodic treatment of the electrode at approximately 3 V for 30 min in case of electrode fouling, which may occur after a prolonged use. Such a treatment damages the glassy carbon (GC) and metal electrodes, while the diamond electrode remains stable. These results suggest that the diamond electrode is superior to the other previously used electrodes such as GC and Kelgraf type for highly sensitive and stable detection of carbamate pesticides.

Carbamates↗

Use of the cross-section technique linked with multivariate calibration methods to resolve complex pesticide mixtures.

The potential of the cross-section (CS) approach in combination with the partial least squares (PLS) and principal component regression (PCR) was assessed in the resolution of a complex pesticide mixture showing twelve overlapped components in High Performance Liquid Chromatography with Diode Array Detection (HPLC-DAD). Careful selection of the CS through the three-dimensional (3D) (A, lambda, t) data matrix gave two-dimensional (2D) signals with the best sensitivity for the determination of each pesticide. In all cases, the application of the PLS method demonstrated a better quantitative prediction ability than that of the PCR method. The CS-PLS approach is a powerful analytical tool. Ten pesticides were well-resolved, while for the other two pesticides of the mixture prediction ability was poor, and they could not be determined, probably due to their low net analytical signal. The CS-PLS model was evaluated by predicting the concentrations of independent test set samples. Finally, the proposed model was successfully applied for the determination of these pesticides in groundwater.

Calibration↗

VOCs, pesticides, nitrate, and their mixtures in groundwater used for drinking water in the United States.

Samples of untreated groundwater from 1255 domestic drinking-water wells and 242 public supply wells were analyzed as part of the National Water-Quality Assessment Program of the U.S. Geological Survey between 1992 and 1999. Wells were sampled to define the regional quality of the groundwater resource and, thus, were distributed geographically across large aquifers, primarily in rural areas. For each sample, as many as 60 volatile organic compounds (VOCs), 83 pesticides, and nitrate were analyzed. On the basis of previous studies, nitrate concentrations as nitrogen > or = 3 mg/L were considered to have an anthropogenic origin. VOCs were detected more frequently (44%) than pesticides (38%) or anthropogenic nitrate (28%). Seventy percent of the samples contained at least one VOC, pesticide, or anthropogenic nitrate; 47% contained at least two compounds; and 33% contained at least three compounds. The combined concentrations of VOCs and pesticides ranged from about 0.001 to 100 microg/L, with a median of 0.02 microg/L. Water from about 12% of the wells contained one or more compounds that exceeded U.S. Environmental Protection Agency drinking-water standards or human health criteria, primarily because of nitrate concentrations exceeding the maximum contaminant level in domestic wells. A mixture is defined as a unique combination of two or more particular compounds, regardless of the presence of other compounds that may occur in the same sample. There were 100 mixtures (significantly associated with agricultural land use) that had a detection frequency between 2% and 19%. There were 302 mixtures (significantly associated with urban land use) that had a detection frequency between 1% and <2%. Only 14 compounds (seven VOCs, six pesticides, and nitrate) contributed over 95% of the detections in these 402 mixtures; however, most samples with these mixtures also contain a variety of other compounds.

Data Collection↗

Analysis of pesticide residues on museum objects repatriated to the Hupa tribe of California.

In the past, it was common practice for museum professionals and private collectors to apply a variety of pesticide agents to objects in their collections to preserve them from depredations by microorganisms, fungi, and other pests. The Native American Graves Repatriation and Protection Act allows federally recognized tribes to request that museums return objects taken from their ancestors. Given that poor records were kept on the treatment of individual objects, it is unknown whether specific objects are contaminated with these pesticide agents. Although chemical analysis represents the only reliable means to determine the types and levels of pesticides on these objects, surprisingly few publications document the extent of this contamination in museum collections. This paper reports on the determination of arsenic, mercury, and several organic pesticides on 17 objects that were recently repatriated to the Hupa tribe in northern California. Four samples were taken from each object: two for arsenic and mercury analysis via flame atomic absorption spectrophotometry and two for organic pesticide analysis via gas chromatography/mass spectrometry. Percent levels (wt/wt) of mercury were detected on many samples, and 0.001 to 0.183% (wt/wt) levels of p-dichlorobenzene, naphthalene, thymol, lindane, and/or DDT were detected on many of the samples. These results indicate that Hupa tribal members should not wear these objects in religious ceremonies, proper precautions should be followed when dealing with potentially contaminated objects, and that more serious consideration should be given to this issue at a national level.

Arsenic↗

Variability assessment of groundwater exposure to pesticides and its consideration in life-cycle assessment.

Pesticide leaching from agricultural fields to groundwater is an environmentally relevant and highly variable process. In the present paper, leaching scenarios typical in European agriculture are defined. These scenarios consider important sources of pesticide leaching variability, namely site factors, farming practice, and substance properties. The logic-tree method was used to structure these scenarios. For each scenario, leached fractions of pesticide applied in agriculture were calculated with data and models used in the registration process of the European Union (EU). Contributions of all parameters to variability were calculated for 11 pesticides. Substance properties (Koc and DT50,soil) contributed the mostto variability, followed by site, weather, season of application, crop, and macropore flow. The results of the variability assessment may be directly applied in policy making or they may be used in the environmental assessment of pesticides, e.g. with the life-cycle assessment (LCA) method. Several approaches are suggested for howthe variability assessment presented in this paper may be incorporated in LCA. The application of these approaches is illustrated by a case study on atrazine.

Europe↗