Levels Of Organochlorine Residues Research Articles

Blood levels of organochlorine residues and risk of breast cancer.

Organochlorines such as DDT [2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane] and PCBs (polychlorinated biphenyls), which have been used extensively as insecticides and as fluid insulators of electrical components, respectively, are known to be persistent environmental contaminants and animal carcinogens. These agents have been found in human tissue due to their inefficient metabolism and their solubility in lipids, which lead to lifelong sequestration in adipose tissue. Their association with human cancer occurrence, however, has been explored only marginally, with most studies having 20 or fewer cases. This blinded study was designed to determine whether exposure to PCBs and to DDE [1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene], the major metabolite of DDT, is associated with breast cancer risk in women. We analyzed sera from the stored blood specimens of 14,290 participants enrolled between 1985 and 1991 in the New York University Women's Health Study, a prospective cohort study of hormones, diet, and cancer. Cohort members who developed breast cancer were included as case patients in our nested case-control study. DDE and PCBs were measured by gas chromatography in the sera of 58 women with a diagnosis of breast cancer 1-6 months after they entered the cohort and in 171 matched control subjects from the same study population who did not develop cancer. Mean levels of DDE and PCBs were higher for breast cancer case patients than for control subjects, but paired differences were statistically significant only for DDE (P = .031). After adjustment for first-degree family history of breast cancer, lifetime lactation, and age at first full-term pregnancy, conditional logistic regression analysis showed a fourfold increase in relative risk of breast cancer for an elevation of serum DDE concentrations from 2.0 ng/mL (10th percentile) to 19.1 ng/mL (90th percentile). For PCBs, the relative risk for a change in serum levels from 3.9 ng/mL (10th percentile) to 10.6 ng/mL (90th percentile) was less than twofold, a nonsignificant association that was further reduced after adjustment for DDE. In this population of New York City women, breast cancer was strongly associated with DDE in serum but not with PCBs. These findings suggest that environmental chemical contamination with organochlorine residues may be an important etiologic factor in breast cancer. Given the widespread dissemination of organochlorine insecticides in the environment and the food chain, the implications are far-reaching for public health intervention worldwide.

Organochlorine insecticide residues in human breast milk: a survey of lactating mothers from a remote area in Papua New Guinea.

In November 1990 a survey team from the Ok Tedi Mining Medical Department collected 50-100 ml samples of breast milk from 41 lactating mothers living in 4 remote villages (altitude 600-1500 m) in the Star Mountains of the Western Province of Papua New Guinea. Almost all of the woman had lived their entire lives in total isolation except for an occasional visit to Tabubil a town between 5-5 days walking distance. The people in these villages grow their own food and practice primitive agricultural techniques (i.e. hunter gatherer/slash and burn). Gas chromatography tests were used to detect levels of organochlorine residues. DDT was present in all breast milk samples. In fact the breast milk of 10 women had DDT levels higher than the allowable limit of 1.25/mg/kg fat for cows milk (1.43-300 mg/kg). Mean total DDT levels were considerably higher in the breast milk of mothers feeding their first child than it was in mothers feeding their second or higher birth order child (1.33 mg/kg vs. .6 mg/kg; p < .001). Younger mothers (< 30 years) had higher mean total DDT/levels than did older mothers (.96 mg/kg vs. .63;l p < .05). 6 mothers had Heptachlor epoxide in their breast milk (.01-.02 mg/kg) but the levels were below the maximum residual concentration of .15 mg/kg fat. These same mothers all had higher than average DDT levels. They did not come from the same village. It is important to note that no spraying of DDT had occurred in or near any of the villages. 11 women had higher DDT levels than DDE levels suggesting recent and/or direct exposure but the researchers could not explain why these women had higher DDT levels. These results show that organochlorines are ubiquitous. The researchers recommend that since the levels were relatively small and breast milk provides many benefits the women continue to breast feed.

Decline of a bat Pipistrellus pipistrellus population in an industrialized area in south Sweden

Two populations of the pipistrelle bat Pipistrellus pipistrellus in southernmost Sweden were studied for eight consecutive breeding seasons using bat boxes. The population living in the vicinity of an industrial area had a declining population trend when compared to that form a rural area. Mass indices in September, when fat accumulation prior to hibernation has started, were also lower compared to those obtained in the rural area. The levels of organochlorine residues and of cadmium were also higher in the population living close to the industrial area. The proximate cause of the decline, however, is assumed to be deteriorating feeding conditions due to drainage and water pollution.

Characteristic trend of persistent organochlorine contamination in wildlife from a tropical agricultural watershed, south India.

The residue levels of persistent organochlorines, such as HCH (BHC: 1,2,3,4,5,6-hexachlorocyclohexane) isomers, DDT [1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane] compounds, PCBs (polychlorobiphenyls) and HCB (hexachlorobenzene), were measured in wildlife. The wildlife were sampled from terrestrial and aquatic habitats in and around the agricultural watershed of Parangipettai, South India. On the basis of overall concentrations sigma HCH ranked first followed by sigma DDT, sigma PCB and HCB, reflecting the increasing usage of HCH in recent years in India. The residue levels of organochlorines in birds varied according to their feeding habits and showed the following pattern: inland piscivores and scavengers greater than coastal piscivores greater than insectivores greater than omnivores greater than granivores. High levels of HCH and DDT residues were recorded in Pond heron and Cattle egret which feed in the agricultural fields. Comparison of HCH concentrations in fish and birds in the study area to other locations was made to further understand the dynamics of contaminant accumulation in tropical wildlife. Regarding birds, a wide variation in residue levels could be seen among various countries, with tropical regions registering high levels. In contrast, the variation is not prominent in the case of fish. The residue levels in fish measured in the present study were generally comparable to values reported from other locations. This suggests that the bioavailability of contaminants to the aquatic fauna is less due to the smaller flux and shorter residence time of these chemicals in the tropics.

Current Status of Contamination by Persistent Organochlorines in the Lower Chao Phraya River, Thailand

Water and sediment samples collected from the lower Chao Phraya River and a canal along the river during 1988 - 1991 were analyzed to determine the current status of contamination by organochlorine pesticides, such as HCHs, DDTs, aldrin, dieldrin and chlordanes. Aldrin and dieldrin had high frequencies of occurrence in water samples. The medians of concentrations of these pesticides were approximately one order of magnitude larger than total HCHs and total DDTs. Residue levels of these pesticides varied significantly. Relatively higher levels of aldrin were observed in the upstream; in contrast, residue levels of DDTs were higher in urban area. These phenomena seem to relate to the spraying purpose of these pesticides. Decreasing trends in the residue levels of pesticides during monitoring periods, however, were not observed clearly. Residue levels of organochlorines in the sediment samples were in the order of magnitude of PCBs, DDTs, chlordanes and HCHs.

Residue levels of organochlorines and mercury in cattle egret, bubulcus ibis, eggs from the Faiyum Oasis, Egypt.

In Egypt, the Cattle Egret Bubulcus ibis is a common resident bird of the Nile Valley, the southern part of the Nile Delta, and the Suez Canal area. In the 1970s it disappeared as a breeding bird from the greater part of the Nile Delta, as did several other bird species, notably birds of prey. Only in recent years some of the species that had declined are markedly recovering, such as the Black-shouldered Kite Elanus caeruleus and the Cattle Egret. There is circumstancial evidence that these birds declined - at least partially - as a result of pesticide use in the main cotton growing areas, but this has never been substantiated. The recent recovery of some bird populations, commencing in the 1980s, coincides with a general shift from the use of organochlorines (except for endrin and HCH which are still in use) towards synthetic pyrethroids, organophosphates and carbamates in Egyptian agriculture: 30 million kg of formulated product annually, of which 70% are applied to cotton. The number of breeding pairs of Cattle Egrets in a well-known colony at Giza (30[degrees].01'N 31[degrees].13'E) steadily declined from 2500 in 1977 to 1100 in 1984. Therefore, it was decided to collect some eggs formore » residue analysis. Cattle Egrets are not piscivores, such as most other egrets, but mainly insectivores. They feed in agricultural areas and likely are good indicators for pesticide use in these habitats. Based on gizzard contents analysis, Kirkpatrick (1925) concluded that Cattle Egrets in Egypt only occasionally take (semi) aquatic prey, such as toads, and further predominantly Orthoptera and Diptera on arable land. Various studies have been published with respect to pesticides or heavy metals in the Egyptian environment but, surprisingly, birds have been almost completely ignored. The data presented are the first residue analyses of bird eggs from an agricultural area in Egypt, and as such they can be considered as baseline data for future research. 36 refs., 2 tabs.« less

Geographical Distribution of Contaminants and Productivity Measures of Herring Gulls in the Great Lakes: Lake Huron 1980

The concentrations of DDE, PCBs (1:1 mix of Aroclor 1254:1260), mirex, HCB, QCB, and tetrachlorobenzenes in eggs of herring gulls are presented for nine colonies in Lake Huron in 1980, as part of intensive investigations of herring gull numbers, biology, and contaminant burdens in that year. Additional data are given for seven other organochlorine contaminants at two colonies. These data are analyzed in relation to eggshell thickness, clutch size and reproductive output, and population trends at sample colonies. Levels of all contaminants measured were markedly lower than during the 1970s, and eggshells were only 6% thinner on average than during the pre-DDT era. Levels of most organochlorine (OC) residues were highest in eggs from Saginaw Bay, which remains one of the most heavily contaminated sites on the Great Lakes. Discriminant function analyses provided reasonably good regional, but not colony-specific, separation of eggs based on suites of OCs. Reproductive output was relatively high, and we found little evidence of impaired reproduction attributable to OC contamination or burden in 1980. Lake-wide, herring gull numbers were increasing slightly, but decreasing at colonies on the main body of Lake Huron.

Organochlorine residue analysis of commercial milks by capillary gas chromatography

AbstractThe determination of organochlorine pesticides and polychlorinated biphenyls in milks requires the use of efficient extraction methods. A rapid procedure has been developed, based on extraction of organochlorine residues from milk on to octadecylsilica solid phase extraction cartridges and elution with hexane. The addition of different organic solvents to the milk before solid phase extraction has been studied. The use of methanol to disrupt the fat globules enables almost complete recovery of the residues with minimum extraction of fatty substances.Recovery experiments were performed for eighteen compounds present at ppb levels in whole, two per cent, and skimmed milks. The average recoveries of the compounds from two per cent and skimmed milks were 73–84%; values for whole milk were lower. The residues were determined by gas chromatography using two kinds of capillary column (non‐polar and semi‐polar) and electron capture detection. The procedure shows low lipid carry over, and extraneous interferences are minimal.The method has been applied to the detection of organochlorine pesticides and nine individual polychlorinated biphenyls in commercial milks. The results obtained demonstrated the presence of very low levels of organochlorine residues in the commercial milks analyzed.

Comparison of organochlorine residue levels in the striped dolphin from western north Pacific, 1978–1979 and 1986

Blubber samples of adult male striped dolphins ( Stenella coeruleoalba) from Pacific coast of Japan collected during 1978–1979 and 1986 were analysed for persistent organochlorines such as PCB isomers and congeners, DDT compounds, HCH (BHC) isomers and HCB for understanding the long-term changes in the residue levels of these contaminants. Comparison of the organochlorine levels using dolphins of same age revealed that the level of contamination remains unchanged in the case of PCBs and DDTs during the above period. Whereas HCHs and HCB showed a significant decrease. Unlike terrestrial animals contaminated in point source and nearby areas, the striped dolphin which is living in remote area from the contamination source exhibited slow temporal trend of organochlorine residue levels. Present data indicate that persistent organochlorine contamination is still continuing in the remote marine environment.

Breeding ecology of the MerlinFalco columbariusin Shetland

The breeding Merlin population in Shetland declined by about 50% between 1981 and 1983, and in 1982 breeding success was low at only 50%. Since then the population has substantially recovered and on average 68% of nesting pairs have been successful. However, 97% of nest failures occurred at the egg stage, with 59% apparently due to egg breakage by the Merlins themselves. The causes of the reduction in population and breeding success are not known; adverse weather conditions and nest predation were unlikely to have been significant, and levels of organochlorine residues and PCBs in addled eggs were low in comparison with Britain as a whole. However, mercury levels were the highest recorded in Britain and may have been implicated in nest failures.

Geographical distribution of contaminants and productivity measures of herring gulls in the great lakes: Lake Erie and connecting channels 1978/1979

The distribution and size of colonies, residue levels of DDE, DDT, HCB, dieldrin, mirex and PCBs in eggs, productivity and eggshell thickness were determined for herring gulls at 14 sites in Lake Erie and connecting channels. The centre of distribution for breeding herring gulls was the Western Basin where approximately 90% of the 6200 nests in the study area were located. Seven of 22 colonies showed an average annual population increase of 48.3%. Most of the increase in breeding herring gulls on Lake Erie is directly associated with sites that have undergone habitat modification by man. Levels of PCBs and DDE ranged from 35 to 140 ppm (wet weight) and from 2.8 to 9.4 ppm, respectively; all other residues were < 0.49 ppm. Most organochlorine residue levels were highest in eggs from colonies in or near the Niagara or Detroit Rivers. Mirex residues were greatest in the Niagara River and decreased significantly to the west. PCB residues were greatest in the Detroit River and decreased significantly to the east. The lowest levels generally came from colonies in the Sandusky Basin and near Pelee Island in western Lake Erie. Discriminant function analysis of six organochlorine contaminants correctly classified 90% or more of the eggs from up to four colonies in one or more years. Levels of PCBs and HCB appeared to have the greatest discriminating power. Herring gull productivity at all colonies (1–1.7 young gulls/pair) was normal and showed no significant geographical variation. Eggshell thickness was greatest in colonies in the Sandusky Basin and least in colonies in the Detroit River and extreme west end of the lake; mean eggshell thickness was 0.350 ± 0.02 mm (6.7% thinning), which was weakly, but significantly correlated to DDE concentration. The variation in contaminants in herring gull eggs on a Basin basis (i.e., Western, Eastern, Sandusky, etc.) paralleled those known for sediments, water and fish. Thus, we suggest that in addition to its role as an indicator of lake-wide contamination of the Great Lakes, the herring gull, under some circumstances, may function as an indicator of “regional” contamination. This is an important distinction as it improves the geographical specificity of the herring gull as an indicator species on the Great Lakes, where it is a non-migratory species.

Pesticide Residues in Milk and Fish Samples Collected from Two Egyptian Governorates

Because of the intensive use of pesticides for the control of certain pests in Egypt, country-wide residue monitoring programs must be established that can cover all the Egyptian Governorates exposed to pesticide treatments. To do so, limited programs must be adopted first, so that current situations and future needs for improved programs are identified. The present paper reports results from a limited monitoring program, which started in 1985 in one governorate and then expanded to include another in 1986. Fish and milk samples were the commodities selected for residue analysis. The results showed that milk samples collected from Beni-Suef Governorate in 1986 had lower levels of organochlorine residues compared to those collected in 1985. Residues in boltifish and catfish samples in 1986 were much higher than those detected in 1985. In comparison with Beni-Suef Governorate, and contrary to expectations, milk derived from Fayoum Governorate in 1986 was more contaminated with pesticides. While the amount of residues in boltifish was comparatively higher, catfish samples were less contaminated.

Organochlorine residues in water from the Mahala water reservoir, Jaipur, India

Residues of p, p′-DDE, p, p′-DDT α-, β-, γ-isomers of HCH, aldrin and heptachlor in water, from four different sites of the Mahala water reservoir were monitored periodically from September 1985 to October 1987. All the samples contained the above residues in varying concentrations. Isomers of HCH predominated and were followed in relative dominance by aldrin, total DDT and heptachlor residues, p, p′-DDE and p, p′-DDD constituted the major fraction of total p, p′-DDT. Monthly total organochlorine residue levels in water ranged between 1·07 and 81·23 μg litre −1 . The variation is attributed to the run-off or subsoil water movement from the catchment area.

Organochlorine residues in human adipose tissue in Spain: Study of an agrarian area

The environmental pollution by persistent organochlorine residues has received much attention in the last years because of its possible effects on wildlife and human health. These residues - organochlorine insecticides, hexa-chlorobenzene (HCB), polychlorinated biphenyls (PCBs) and, in minor levels, polychlorinated dibenzofurans (PCDFs) and dibenzodioxins (PCDDs) - are accumulated in lipid-rich tissues. Their concentrations in adipose tissues of human populations are the best indices in determining the extent of exposure and in evaluating the hazard. In a previous study on the urban population of Barcelona (Spain) during the years 1982-83, high levels of DDE, DDT, /beta/-HCH and HCB were determined. Recently the incidence of HCB in Barcelona has been confirmed by serum determinations. In the present paper the authors have investigated the levels of organochlorine residues - with special concern on HCB- in human adipose tissues from an agrarian area, located at 130 km from Barcelona, mainly devoted to fruit-trees and cereal culture. Results obtained will form part of an up-to-date report on organochlorine pollution in Spain, including several populations of different geographical and socioeconomic characteristics, that will make it possible to identify the sources and trends of this contamination.

Organochlorine contaminants in eggs of common terns from the Canadian Great Lakes, 1981

To determine if contaminant levels in Common Terns had changed over the last decade, we collected and analyzed eggs from four nesting colonies on the three lower Great Lakes during 1981. DDE and PCBs were detected in every egg from the four colonies. Dieldrin, mirex and trans-nonachlor were detected in more than 45% of the eggs. Seven other organochlorine contaminants (DDD, DDT, hexachlorobenzene, oxychlordane, cis-chlordane, cis-nonachlor and toxaphene) were detected in less than 25% of the eggs. Eggs from the Lake Ontario colony were generally the most heavily contaminated. Comparisons of DDE and PCB data with earlier studies of Common Terns indicated that contaminant levels in eggs from the four sampled colonies, or nearby sites, have decreased by up to 80–90% from 1969–1973 to 1981. Interspecies comparisons showed that Common Tern eggs have lower organochlorine residue levels than eggs of Caspian Terns or Herring Gulls. Dietary variation and migratory status are possible explanations for the differences in residue levels among species. Eggshell thickness, log-PCBs, and log-DDE were not significantly intercorrelated. Elevated contaminant levels in the early 1970s might be at least partly responsible for the decline of the Great Lakes Common Tern population over the past decade. Stabilization of population numbers during the early 1980s suggests that organochlorine pollution levels have been reduced to a point where they are no longer an important factor in the population dynamics of this species on the Great Lakes.

Organochlorine pesticides and polychlorinated biphenyls in maternal adipose tissue, blood, milk, and cord blood from mothers and their infants living in Norway.

Samples of maternal blood, milk, and umbilical cord blood were collected from mothers and their infants at Ulleval University Hospital in Oslo, Norway. All the mothers had lived in Oslo during the last two years. Of the Norwegian mothers, 16 were delivered by Caesarean operation, and samples of subcutaneous fat tissues were collected. Hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs),p,p′-DDE,p,p′-DDT, and dieldrin were found in 157, 135, 168, 22, and 12, respectively, of the 168 samples analyzed, while β, and γ-hexachlorocyclohexane (HCH) were found in 93 and 26, respectively, of the 152 samples analyzed for these compounds. In the samples obtained from the Norwegian mothers and infants, PCBs andp,p′-DDE were the major contaminants present. In contrast, only traces of PCBs were found in six immigrant samples, which, however, contained 4–6 times higher levels ofp,p′-DDE plusp,p′-DDT than the corresponding Norwegian samples. Of the HCH isomers, the β-HCH was the predominant isomer present. Two to three times significantly higherp,p′-DDE and PCBs levels were found in maternal serum than cord serum. No significant differences were found between the organochlorine residue levels in subcutaneous fat and milk fat. A significant positive linear correlation was found between the levels ofp,p′-DDE and PCBs in maternal serum and in milk fat, and between the levels ofp,p′-DDE in maternal serum and cord serum from Norwegian mothers giving birth normally. Significantly higher PCBs andp,p′-DDE residues were found in the maternal and cord serum samples obtained after Caesarean operation than after normal delivery, while no other such differences were found in the milk samples 5 days post partum. The results demonstrate that organochlorines are transferred from mother to fetus and newborn babies through the placenta and milk and that human milk is a good indicator in monitoring human beings and their environment for organochlorine contamination. Possible toxicological implications of the present results are discussed.

Organochlorine residue levels in three high arctic species of colonially-breeding seabirds from Prince Leopold Island

Levels of DDE and PCB residues in Northern Fulmar Fulmarus glacialis, Black-legged Kittiwake Rissa tridactyla and Thick-billed Murre Uria lomvia collected at Prince Leopold Island, Northwest Territories, between 1975 and 1977 are relatively low. Organochlorine levels were highest in all species in 1976, a year when lipid levels in all tissue examined (adult and chick liver, egg) were highest. Annual variation of DDE and PCB may thus be largely due to differences in nutritional and associated environmental conditions. The unusually high PCB/DDE ratio for the kittiwake cannot be explained by low DDE concentrations rather than by high concentrations of PCBs as suggested else-where. Data from Prince Leopold Island birds indicate both that DDE concentrations are low and that PCB concentrations are high. The evidence seems to suggest a differential ability by the kittiwake to metabolize and excrete organochlorines as compared to other seabirds. The data form an important baseline for high arctic colonially-breeding seabirds in Canada against which future organochlorine levels can be compared.

Organochlorine pesticides and polychlorinated biphenyls in human milk during lactation

Organochlorine residue levels were determined in human milk samples of 5 women. The contaminants analyzed were: α-, β-, and δ-hexachlorocyclohexane (HCH), hexachlorobenzene (HCB), p,p′-DDT, p,p′-DDE, and polychlorinated biphenyls (PCB's). The variation of residue levels in human milk during lactation was investigated for each woman individually. Month-mix samples composed of weekly collected breast milk samples were analyzed over a lactation period between 5 and 9 months. No essential changes in organochlorine residue levels in human milk occurred over the lactation periods investigated; the concentration remained either relatively constant or showed fluctuations with no observable trend.

Pesticide pollution of soil, water and air in Delhi area, India

In India organochlorine insecticides such as DDT and HCH constitute more than 70% of the pesticides used at present. Its continued use has given interest to monitor for the last few years the extent of organochlorine insecticide residues in soil, water, air and rain water in Delhi area. Out of the 50 samples each of soil and earthworms collected from different parts 48 samples showed that soil and earthworms contained 0–2.61 and 0–37.74 mg Kg −1 of total DDT residues respectively. The area near the vicinity of the DDT factory showed high levels of DDT residues. A two-year survey of the Yamuna river in Delhi showed that water contained an average of 0.24 mg Kg −1 of total DDT residues. The bottom sediment had 0.24 mg Kg −1 of total DDT residues. The fishes collected from the Yamuna river showed very high bioaccumulation of DDT residues. The air and rainwater samples monitored from 3 different areas for two years indicated that DDT was more near the DDT factory area while HCH was more near a commercial complex. These results indicate that the overall organochlorine-residue levels in Delhi is not alarming. It probably indicates that DDT and HCH are more rapidly dissipated and degraded in a tropical country like India.

Characterization of mixed‐function oxidase systems of the nestling herring gull and its implications for bioeffects monitoring

AbstractThe hepatic mixed‐function oxidase system was characterized in embryonic and nestling herring gulls (Larus argentatus). The activity of aminopyrine N‐demethylase decreased significantly with the age of the nestlings. No consistent changes in 7‐ethyoxyresorufin O‐deethylase, benzo[a]pyrene 3‐hydroxylase or cytochrome P450 levels with age were found. Levels of organochlorines were determined in individual livers for the 21‐d‐old nestlings. Correlations among organochlorine residue levels were good, and the activities of aminopyrine N‐demethylase and benzo[a]pyrene 3‐hydroxylase correlated with each other and with cytochrome P450 levels. No correlations were found with 7‐ethoxyresorufin O‐deethylase activity, and none of the enzyme levels correlated with the organochlorine residue levels. However, cytochrome P450 levels correlated with both hexachlorobenzene and oxychlordane levels. The implications for the use of the mixed‐function oxidase system for environmental monitoring of exposure to organochlorines and polynuclear aromatic hydrocarbons are discussed.