Low Levels Of Organochlorine Pesticides Research Articles

Exposure to DDT and HCH congeners and associated potential health risks through khat (Catha edulis) consumption among adults in South Wollo, Ethiopia

Khat (Catha edulis) chewing is widespread in the region of East Africa. Even low levels of organochlorine pesticides (OCPs) in khat could induce public health concern. In a market-based study, from five popular khat varieties, a total of 35 composite khat samples were analyzed for dichlorodiphenyltrichloroethane (DDT) and its main transformation products, and four hexachlorocyclohexane (HCH) isomers. Extraction was carried out by quick, easy, cheap, effective, rugged and safe method (QuEChERS). OCP concentrations were determined by head space solid phase microextraction coupled to gas chromatography-mass spectrometry (HS-SPME–GC–MS). Every sample contained β-HCH above the maximum residue limit set by the European Commission. For total DDT, this was the case for 25.7% of the samples. The ratios of (p,p′-DDD + p,p′-DDE) to p,p′-DDT were less than one for 85% of khat samples, demonstrating recent use of DDT in khat farmlands. Conversely, the ratio of β-HCH to total HCH varied from 0.56 to 0.96, implying historical input of technical HCH. Assuming a daily chewable portion of 100 g, dietary intakes of p,p′-DDT, total DDT and total HCH by adults ranged from 3.12 to 57.9, 6.49 to 80.2 and 39.2 to 51.9 ng (kg body weight)−1 day−1, respectively. These levels are below acceptable levels suggested by international organizations. Chewing khat showed lower non-cancer health risk, but showed relatively higher cancer risk in terms of OCPs. Because khat is chewed without being subjected to any treatment, uncertainties associated with estimated intakes and health risks should be low. Therefore, this practice is of great concern.

Association between prenatal exposure to organochlorine pesticides and the mental and psychomotor development of infants at ages 6 and 18 months: The Hokkaido Study on Environment and Children’s Health

Organochlorine pesticides (OCPs) are environmental contaminants that persist in the environment and bioaccumulate through the food chain in humans and animals. Although previous studies have shown an association between prenatal OCP exposure and subsequent neurodevelopment, the levels of OCPs included in these studies were inconsistent. A hospital-based prospective birth cohort study was conducted to examine the associations between prenatal exposure to relatively low levels of OCPs and neurodevelopment in infants at 6 (n=164) and 18 (n=115)months of age. Blood samples were analyzed using gas chromatography/mass spectrometry techniques to quantify 29 OCPs. The Bayley Scales of Infant Development 2nd edition (BSID-II) was used to assess the Mental and Psychomotor Developmental Index. After controlling for confounders, we found an inverse association between prenatal exposure to cis-heptachlor epoxide and the Mental Developmental Index at 18 months of age. Furthermore, infants born to mothers with prenatal concentrations of cis-heptachlor epoxide in the highest quartile had Mental Developmental Index scores −9.8 (95% confidence interval: −16.4, −3.1) lower than that recorded for infants born to mothers with concentrations of cis-heptachlor epoxide in the first quartile (p for trend <0.01). These results support the hypothesis that prenatal exposure to OCPs, especially cis-heptachlor epoxide, may have an adverse effect on the neurodevelopment of infants at specific ages, even at low levels.

Spatial distributions, source apportionment and ecological risk of SVOCs in water and sediment from Xijiang River, Pearl River Delta.

Xijiang River is an important drinking water source in Guangxi Province, China. Along the Xijiang River and surrounding tributary, the pollution profile of three important groups of semi-volatile organic compounds, including polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and phthalate esters (PAEs), was analyzed. Relatively low levels of PAHs (64-3.7×102ngL-1) and OCPs (16-70ngL-1), but high levels of PAEs (7.9×102-6.8×103ngL-1) occurred in the water. Comparatively, low levels of OCPs (39-1.8×102ngg-1) and PAEs (21-81ngg-1), but high levels of PAHs (41-1.1×103ngg-1) were found in sediment. Principal component analyses for source identification indicated petroleum-derived residues or coal and biomass combustion, and vehicular emission was the main sources for PAHs. The OCPs sources of each category were almost independent, whereas the new input of HCHs and p,p'-DDTs probably existed in some areas. PAEs were mainly originated from personal care products of urban sewage, plastic and other industrial sources. Ecological risk through the risk quotient analysis indicated a small or significant potential adverse effect on fish, daphnia and green algae. Nevertheless, the integrated risk of all pollutants should be taken into account in future study.

Organochlorine Pesticides, Polychlorinated Biphenyls, Seafood Consumption, and Time-to-Pregnancy

People in developed countries are widely exposed to low levels of organochlorine pesticides, polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs). Seafood is a major contributor to PCB exposure. Toxicity of those various pollutants to reproductive and endocrine functions raises questions about possible effects on fertility. We explored whether serum levels of these pollutants and seafood consumption were associated with the fertility of couples enrolled in a French birth cohort (PELAGIE). Time-to-pregnancy was investigated in 3,421 pregnant women by asking how many months they had taken to conceive. Levels of 14 organochlorine pesticides, 12 PCBs, and 10 PBDE compounds were measured in cord blood serum from a random subcohort (n = 394). Mercury concentrations measured in maternal hair were considered as a potential coexposure. Fecundability odds ratios (ORs) were estimated from multivariate discrete-time Cox proportional hazard models. Shellfish consumption was associated with longer time-to-pregnancy (fecundability OR ≥twice/week vs. <twice/month = 0.71 [95% confidence interval = 0.60-0.83]), but fish consumption was not. Time-to-pregnancy increased with increasing serum levels for most of the compounds studied (for total PCBs >0.410 µg/L vs. <0.266 µg/L, fecundability OR = 0.46 [0.32-0.66]). In multiple sensitivity analyses, reduced fecundability was most consistently associated with shellfish consumption, p,p'-DDE, total PCBs, PCB153, and PCB187. Models that simultaneously included multiple coexposure factors led to similar conclusions. Our findings were robust in sensitivity analyses, including analysis restricted to primiparous women. These results suggest that PCBs, p,p'-DDE, and other shellfish contaminants may impair human fertility.

Deposition of organochlorine pesticides into the surface snow of East Antarctica

Organochlorine pesticides (OCPs) were measured in surface snow collected on a ~1400-km inland traverse beginning from the coastal regions of East Antarctica during the Japanese Antarctic Research Expedition (JARE) of 2007/2008. Of the 22 OCPs, α-hexachlorocyclohexane (HCH), γ-HCH, and hexachlorobenzene (HCB) were frequently detected in the snow with concentration ranges of 17.5–83.2, 33–137, and ND–182pgL−1, respectively. The most abundant pesticide was γ-HCH, with a mean concentration of 69.9pgL−1, followed by α-HCH, with an average concentration of 44.5pgL−1. The spatial variability of α-HCH and γ-HCH was narrow, and the concentrations of α-HCH and γ-HCH increased slightly with increasing altitude along the traverse route. Dome Fuji, the highest altitude sampling point, had the highest γ-HCH concentrations in the snow. Backward air trajectory analysis showed that the air masses at the sampling sites came mainly from the Indian and Atlantic Oceans and over the Antarctic continent, indicating that the OCPs were subjected to long-range atmospheric transport and were deposited in the surface snow. Our data suggest that the snow of Antarctica contains low levels of OCPs.

Persistent Organic Pollutant Residues in Human Fetal Liver and Placenta from Greater Montreal, Quebec: A Longitudinal Study from 1998 through 2006

BackgroundThere is general concern that persistent organic pollutants (POPs) found in the environment, wildlife, food, water, house dust, human tissues, and fluids may alter normal human physiologic activities (e.g., fetal development, immune and endocrine systems). Although the levels of some POPs [polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCs)] in these matrices have decreased after their ban, others [polybrominated diphenyl ethers (PBDEs)] have increased in recent years.ObjectiveTo determine the longitudinal trend of specific POPs in human fetal tissues for risk assessment purposes.MethodsWe analyzed early to mid-gestation fetal liver (n = 52) and placental (n = 60) tissues, obtained after elective abortions during 1998–2006, for selected PBDEs, PCBs, and OCs using gas chromatography–mass spectroscopy.ResultsTotal PBDEs in fetal liver increased over time (mean ± SE: 1998, 284.4 ± 229.8 ng/g lipid; 2006, 1,607.7 ± 605.9; p < 0.03), whereas placental levels were generally lower, with no clear trend. Low levels of PCBs and OCs varied yearly, with no evident trend. The major analytes in 1998 were OCs (liver, 49%; placenta, 71%), whereas the major analytes in 2006 were PBDEs (liver, 89%; placenta, 98%). The 1998–2006 tissue PBDE congener profile is similar to that of DE-71, a commercial primarily pentabrominated diphenyl ether mixture manufactured in North America.ConclusionsAlthough commercial production of penta- and octa-brominated diphenyl ethers in North America was halted in 2004, their concentrations in fetal liver and placenta are now greater than the tissue burdens for the analyzed OCs and PCBs. Our findings also demonstrate that PBDEs accumulate within the fetal compartment at a very early stage in gestation.

Quantification of low levels of organochlorine pesticides using small volumes (≤100 μl) of plasma of wild birds through gas chromatography negative chemical ionization mass spectrometry

A solid phase extraction and gas chromatography with negative chemical ionization mass spectrometry in scan mode (GC-NCI-MS) method was developed to identify and quantify for the first time low levels of organochlorine pesticides (OCs) in plasma samples of less than 100 μl from wild birds. The method detection limits ranged from 0.012 to 0.102 pg/μl and the method reporting limit from 0.036 to 0.307 pg/μl for α, γ, β and δ-hexachlorocyclohexane (HCH), heptachlor, aldrin, heptachlor epoxide, endosulfan I, 1,1-dichloro-2,2-bis( p-chlorophenyl)ethylene ( p, p′-DDE), dieldrin, endrin, endosulfan-II, endrin-aldehyde and endosulfan-sulfate. Pesticide levels in small serum samples from individual Falco sparverius, Sturnella neglecta, Mimus polyglottos and Columbina passerina were quantified. Concentrations ranged from not detected (n/d) to 204.9 pg/μl for some OC pesticides. All levels in the food web in and around cultivated areas showed the presence of pesticides notwithstanding the small areas for agriculture existing in the desert of Baja California peninsula.

Nutritional quality and safety of European perch ( Perca fluviatilis) from three lakes of Central Italy

European perch ( Perca fluviatilis) harvested from three lakes of Central Italy were studied in different seasonal periods of a year to evaluate their nutritional quality and some safety aspects related to the pollution of the aquatic environment. The lakes considered, located in the Latium region, differed with respect to their volcanic (Bolsena and Bracciano Lakes) or artificial (Salto Lake) origin. Fillets of fish caught in the three lakes were characterised by good protein (17–19%) and mineral contents and low lipid levels (0.6–1.2%) throughout the year. Total lipids were characterised by low cholesterol levels (41.9–74.7 mg/100 g) and high percentages of total n − 3 polyunsaturated fatty acids (27.7–33.8% of total fatty acids), in particular docosahexaenoic acid (14.2–25.3% of total fatty acids). The qualitative analysis of the stomach content of perch confirmed their predatory feeding behaviour. The chemical and nutritional profiles of perch from the three lakes were comparable except for rubidium and cesium levels, which were higher in the muscle tissues of perch from the volcanic lakes. These minerals may represent elements of traceability of the origin of fish. Low levels of organochlorine pesticides and polychlorinated biphenyls, well below the Italian and European action limits, were detected in the muscle tissue of perch from all three lakes.

Environmental Occurrence of Organochlorines in the East Coast of Thailand

The measurements of organochlorine pesticides in mussels and oysters collected along the east coast of Thailand indicate that DDTs, chlordanes (CHLs), hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB) are the main organochlorine residues. The results of the study revealed that DDT residues were present in the highest concentration in green mussels and oysters, followed by CHLs, HCHs, and HCB. However, the residue levels in the present study were much lower than those found elsewhere in the tropical coastal water of Asia. Polychlorinated biphenyls (PCBs) were present also in high concentrations in urban and industrial areas. It is interesting that tetra-, penta-, hexa- and hepta-chlorinated isomers were the predominant homologues in both the mussel and oyster samples. The PCB profile in the sediment column from the study area, reflects the active use of PCBs along the east coast of Thailand during the period of 1972-1992. Considering the low levels of organochlorine pesticides (OCs) and PCBs in green mussels and oysters found in this study, the contamination from these organic pollutants in the study area is not particularly serious in the view of human health and ecosystem perspectives.

Low levels of organochlorine pesticides in subjects with metabolic disturbances: a survey taken in Rome in 2001-2002.

Metabolic Disturbances: A Survey Taken in Rome in 2001–2002 D. A. Barbini, F. Vanni, P. Pelosi, T. Generali, G. Amendola, P. Stefanelli, S. Girolimetti, A. Di Muccio, A. Mantovani, G. Spera, L. Silvestroni 1 Department Environment and Primary Prevention, ISS–National Institute of Health, Viale Regina Elena, 299-00161 Rome, Italy 2 Department Food and Animal Safety, ISS–National Institute of Health, Viale Regina Elena, 299-00161 Rome, Italy 3 Department of Medical Pathophysiology, University of Rome “La Sapienza,” Viale Regina Elena, 249-00161 Rome, Italy

Pesticide Residues in Selected Food Commodities: Results from the Danish National Pesticide Monitoring Program 1995-1996

The paper presents results of analyses of 4182 samples collected from January 1995 to December 1996 for the Danish National Pesticide Monitoring Program. The program basis is a random sample control supplemented with a target control. The objectives of the control are to monitor consumer exposure to health hazards and to enforce national and European Community regulations. The Danish Veterinary and Food Administration is responsible for establishing methods, data manipulation, and evaluation, but actual analyses are performed at 4 regional laboratories. In addition to a description of the Danish National Pesticide Monitoring Program on food, the effects of lowering the reporting limits are discussed. Pesticides included are those in current use as well as chlorinated pesticides like lindane, DDT, and HCB, occurring in food now primarily as a result of environmental contamination. Commodities analyzed are fruits, vegetables, cereals, bran, fish, and animal products such as meat, butter, cheese, fat, and eggs. In fruits and vegetables, residues were detected in 10% of 2515 samples, with higher incidences of detection for foreign commodities. Violation rate was 0.6%. In food of animal origin, low levels of organochlorine pesticides were detected in most fish samples and in more than half of the animal product samples. However, no results exceeding maximum residue limits were found. No residues of organophosphorus pesticides were detected in the 231 meat samples analyzed.

Detection of brominated and chlorinated organics by a gas chromatographic microcoulometric detector : Effect of pyrolysis tube conditions

The specific detection of halogenated organics is of considerable interest to environmental scientists. Low levels of organochlorine pesticides, polychlorinated biphenyls (PCBs), and polybrominated biphenyls (PBBs) entering the environment are important because of their refractory nature and potential for bioaccumulation. Low levels of some other halogenated compounds, such as haloforms, which are produced during the chlorine disinfection of waterre3 must be monitored because they may be directly ingested by humans. Gas chromatography (GC) with an electron-capture detector (ECD) is often used for the analysis of haloforms extracted from water&‘, as well as organochlorine pesticides, PCB, and PBB residues 6_ The ECD is used because of its sensitivity for halogenated compounds and its wide availability. The ECD has some disadvantages including: a lack of specificity; widely varying sensitivity with degree of chlorination, e.g. the ECD is 10’ times more sensitive to CHCI, than to CH,Cl (ref. 7); and sensitivity which varies with positional isomerism, e.g. different sensitivity for PCB isomers having the same degree of chlorination ‘. Microcoulometric detection does not have these disadvantages. The microcoulometric detector responds to the weight of halogen present. Through oxidative pyrolysis the material is converted to titratable halides which are swept into the microcoulometric detector cell where the halides react with the silver ions present in the cell electrolyte. The efficiency of this pyrolysis process varies with compound, pyrolysis temperature, and furnace atmosphere. The coulometer produces a voltage proportional to the current required to replace the consumed silver ions. The detector has a selectivity of IO6 for chlorine over carbon and of lo4 for chlorine over sulfur, nitrogen and phosphorusg. Microcoulometric detection has been used to measure total organic halogen as a water quality parameter using a system with a sample boat for sample introduction’*. In this paper the use of a commercially available microcoulometric detector specifically designed as a GC detector, the Envirotech (Santa Clara, CA, U.S.A.)