OBJECTIVE: Exposure to environmental organochlorines has been examined as a potential risk factor for human breast cancer with mixed results. Our purpose was to examine associations between organochlorines and the development of breast cancer in a large prospective study using stored adipose tissue. METHODS: We conducted a nested case-control study of 409 postmenopausal women who developed breast cancer and 409 controls selected from the 29,875 women enrolled in the Danish Diet, Cancer, and Health cohort between 1993 and 1997. We measured concentrations of 14 pesticides and 18 polychlorinated biphenyls in adipose tissue, collected upon enrollment, and estimated relative risk (RR) of breast cancer using conditional logistic regression. RESULTS: The results showed no higher risk of breast cancer among women with higher levels of any pesticides or polychlorinated biphenyls; the RR associated with the upper quartile of 1,1-dichloro-2, 2-bis(p-chlorophenyl)ethylene concentration was 0.7 [95% confidence interval (95% CI), 0.5-1.2] contrasting the lower quartile, and for the sum of polychlorinated biphenyls the similar risk was 1.1 (95% CI, 0.7-1.7). We observed a pattern of substantially lower risk of estrogen receptor-negative breast cancer in association with higher levels of most of the pesticides and polychlorinated biphenyls; the RR for the higher quartile of 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene was 0.1 (95% CI, 0.0-0.5) and for the sum of polychlorinated biphenyls it was 0.3 (95% CI, 0.1-0.9). CONCLUSION: The results do not support that higher organochlorine body levels increase the risk of breast cancer in postmenopausal women. The interpretation of the inverse association for estrogen receptor-negative breast cancer is currently unclear.
Recommended Dietary Allowances (RDAs) are allocated to each food article as published in the Denmark Budget Methods in the Codex Alimentalius of the WHO/FAO Joint Committee when standards of pollutants in food are needed. When daily intakes of Food Additives and Contaminants need to be calculated, the Theoretical Maximum Daily Intake. (TMDI) and the Estimated Maximum Daily Intake (EMDI) have been generally used. TMDI and EMDI are calculated using the formulae shown below: [formula: see text] i: food article (i = 1, ....., n) A: standard value for food additives and contaminants X: mean weight of food article consumed daily l: rate of residue after cooking Exposure assessment should be more exact in order to meet social health needs and to help avoid unnecessarily strict regulations. The U. S. Food and Drug Administration (FDA) is continually improving its estimates of the dietary intakes of pesticides and essential minerals, and comparing these intakes with established safe or recommended dietary intake levels. Dietary survey methods have also improved in parallel, with examples being the USDA's Household Food Consumption Survey (1955 and 1965) and National Health and Nutrition Examination Survey II (1976-1980). In Japan, TMDI and EMDI have received more attention as methods of estimating the daily intakes of food additives and contaminants than has the Total Diet Study, even though the former are not as exact as the latter. The Japanese National Nutrition Survey is one of the most respected nutrition surveys in the world, because it has continued nationwide yearly since 1946. Nevertheless, it is very unfortunate that no one utilizes the Household Food Consumption Survey data for the estimation of intakes of food additives and contaminants, because that is not the primary purpose of the Japanese National Nutrition Survey. Practically, there are neither foods which have an uniform of food additives and contaminants nor individuals who consume uniform amounts of each food item. In this report the authors propose a revised estimation method for the daily intake of food contaminants and additives, based on food consumption data of 159 female volunteers, without using the National Nutrition Survey data. The results obtained are as follows: 1) This method succeeded in making clear the intakes of food additives and contaminants. Mean, maximum and minimum values and distribution curves for the target population were obtained. 2) The suggested name for this method is "Estimated Ecological Daily Intake (EEDI)", which is processed in terms of the food consumption structure for calculation, and methodologically estimated by food ecology.
To study problems associated with pesticide container disposal, a small vegetable production area in southwestern Ontario, the Thedford Marsh, was selected as the site for a model study. A container collection system was organized during the 1981 growing season, with collections being made from the ca. 50 growers on the marsh twice each month. In addition to the regular collection program a cleanup service for empty pesticide containers stored on farms or discarded on public lands also was initiated. More than 3600 containers were collected and disposed of at an authorized landfill site. Ca. 2/3 were herbicide containers, ca. 1/4 were insecticide containers, and 3% were fungicide containers. Unrinsed containers contained as much as 5 1/2% of the original contents with an average of 1%. Containers rinsed by the triple rinse method or using rinsing devices (E-Z Rinse, JET Rinse) generally contained less than 0.1% of the original content. Some formulations presented rinsing problems due to settling and caking. The results indicated that, while unacceptable quantities of pesticide residues remain in unrinsed containers, most rinsed pesticide containers will be acceptable for disposal at municipal sanitary landfill sites.
As a contribution to the FAO/WHO organochlorine monitoring programme, samples of milk, eggs, beef pork, chops, game, animal livers as well as fish-liver oils were analysed for PCB-, DDT- and toxaphene compounds, hexachlorobenzene (HCB), heptachlor and hexachlorocyclohexanes (HCH). From the annual consumption of the foodstuffs investigated average intakes of organochlorines were estimated and compared with the acceptable daily intakes (ADI) as set by FAO/WHO. Intakes from the sources studied were then compared with those from fish, butter and margarine. Total average dietary intakes were determined to be 14.4 micrograms/day for PCB, 2.9 for DDT, 2,3 for gamma-HCH, 1.7 for HCB, and 0.5 micrograms/day for heptachlor representing 0.08% of the ADI for DDT, 0.3% for HCH, 4.2% for HCB and 1.4% of the ADI for heptachlor.
Biobeds originated in Sweden in response to the need for simple and effective methods to minimize environmental contamination from pesticide use, especially when filling spraying equipment, a typical point source of contamination. The biobed system has attracted attention in several countries, where work is being conducted to adapt it to local conditions and applications. As a consequence, the biobed system has been more or less modified and sometimes renamed, for example, as biomassbed in Italy, biofilter in Belgium, and Phytobac and biobac in France. The effectiveness and simplicity of the biobed also make it suitable for use in developing countries, and different adaptations of the biobed concept now exist in, for instance, Peru, Guatemala, and Ecuador. When the modification of the biobed includes an intention to use it for retention and degradation of pesticides in sprayer washings, the construction has to be adapted to, for example, lined biobeds to ensure that no pesticide leaching will occur. Replacement of some of the original materials in the Swedish biomixture (straw, peat, and soil) can also change the performance of the system, for instance, the amount, activity, and composition of the microbial community that develops. This review presents the state of the art of biobeds and similar systems in Sweden and worldwide and identifies future research needs. Factors affecting the efficiency of biobeds in terms of degradation and retention of pesticides are discussed, with particular emphasis on the microbial processes involved.
Numerous studies have examined the relationship between organochlorines and breast cancer, but the results are not consistent. In most studies, organochlorines were measured in serum, but levels in breast adipose tissue are higher and represent cumulative internal exposure at the target site for breast cancer. Therefore, a hospital-based case-control study was conducted in Ontario, Canada to evaluate the association between breast cancer risk and breast adipose tissue concentrations of several organochlorines. Women scheduled for excision biopsy of the breast were enrolled and completed a questionnaire. The biopsy tissue of 217 cases and 213 benign controls frequency matched by study site and age in 5-year groups was analyzed for 14 polychlorinated biphenyl (PCB) congeners, total PCBs, and 10 other organochlorines, including p,p'-1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene. Multiple logistic regression was used to assess the magnitude of risk. While adjusting for age, menopausal status, and other factors, odds ratios (ORs) were above 1.0 for almost all organochlorines except five pesticide residues. The ORs were above two in the highest concentration categories of PCB congeners 105 and 118, and the ORs for these PCBs increased linearly across categories (Ps for trend
The Canadian Total Diet Study is a national survey to determine the level of chemical contaminants in the Canadian food supply. Food samples were collected from Whitehorse, Yukon, supermarkets as part of the study in 1998. Whitehorse was chosen as a sampling centre, despite its small population (n = 19,000), to determine if residue levels were different in foods available in northern communities relative to levels observed in previous studies in the more populated south. Foods were prepared as for consumption before pesticide residue analysis. Residue levels observed in most foods were similar to levels observed in samples from previous surveys from southern Canadian cities. Malathion and DDE (1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene), a transformation product of DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl(ethane), were the two most frequently detected compounds (26.4 and 25.8%, respectively). The majority of pesticides, however, had a detection frequency of