-
Environmental Health Perspectives Aug 2006We recently reported a link between use of the organophosphate pesticide phorate and risk of prostate cancer among applicators with a family history of prostate cancer...
BACKGROUND
We recently reported a link between use of the organophosphate pesticide phorate and risk of prostate cancer among applicators with a family history of prostate cancer in the Agricultural Health Study (AHS).
OBJECTIVE
This finding, together with findings of associations between other organophosphate pesticides and cancer more broadly, prompted us to examine phorate exposure and overall cancer incidence in the AHS. Adding 3 years of follow-up and using more detailed exposure information allowed us to see whether the prostate cancer finding held.
METHODS
The AHS is a prospective study of licensed restricted-use pesticide applicators from North Carolina and Iowa. To our knowledge, this is the largest examination of workers occupationally exposed to phorate. Pesticide exposure and other information was collected using two self-administered questionnaires completed from 1993 to 1997. Poisson regression was used to calculate rate ratios (RR) and 95% confidence intervals (CI), adjusting for potential confounders.
RESULTS
Phorate use was not related to the incidence of all cancers combined or to any individual cancer, although we had insufficient numbers to study non-Hodgkin lymphoma or leukemia, which have been linked to organophosphates in other studies. Although prostate cancer risk was not significantly related to phorate use overall or among those without a family history, the risk tended to increase among applicators with a family history of prostate cancer. The interaction RR was 1.53 (95% CI, 0.99-2.37).
CONCLUSION
The observed statistical interaction suggests a gene-environment interaction between family history and phorate exposure in the incidence of prostate cancer, but other explanations are also possible.
Topics: Adult; Aged; Agricultural Workers' Diseases; Alcohol Drinking; Cohort Studies; Follow-Up Studies; Humans; Insecticides; Iowa; Male; Middle Aged; North Carolina; Occupational Exposure; Phorate; Prostatic Neoplasms; Socioeconomic Factors; Surveys and Questionnaires; Zea mays
PubMed: 16882526
DOI: 10.1289/ehp.8911 -
Journal of Nematology Dec 2003Alternatives to reduce or modify nematicide use for minimizing groundwater contamination in Easter lily were explored in two field trials. Alternatives to standard...
Alternatives to reduce or modify nematicide use for minimizing groundwater contamination in Easter lily were explored in two field trials. Alternatives to standard 1,3-dichloropropene (1,3-D) plus phorate injection in the first trial were: (i) delaying applications until after winter rains, (ii) removing roots from planting stock, (iii) 1,3-D via drip irrigation, (iv) a chitin-urea soil amendment, (v) the registered insecticide disulfoton, and (vi) several nonregistered nematicides. None of the treatments equaled the standard treatment. In the second trial, potential benefits of adding a systemic nematicide, oxamyl (OX), or a fungicide, metalaxyl (MX), to the standard treatment were explored. Preplant drip irrigation applications of metam sodium (MS), sodium tetrathiocarbonate (ST), and emulsifiable 1,3-D were evaluated alone and in combination with postplant applications of OX and MX. Several drip-applied treatments performed comparably to the standard treatment with respect to the most important criteria of crop quality, bulb circumference. Metam-sodium in combination with either or both OX and MX, 1,3-D plus OX and MX, and ST plus OX and MX provided the best results.
PubMed: 19262778
DOI: No ID Found -
Journal of Nematology Dec 2000A survey conducted from May 1995 through August 1998 revealed diverse nematode communities in Louisiana sugarcane fields. High populations of Mesocriconema,...
A survey conducted from May 1995 through August 1998 revealed diverse nematode communities in Louisiana sugarcane fields. High populations of Mesocriconema, Paratrichodorus, Pratylenchus, and Tylenchorhynchus were widespread in nine sugarcane production parishes. Comparisons of plant cane and ratoon sugarcane crops indicated that nematode community levels increase significantly in successive ratoon crops. Nematicide trials evaluated the efficacy of aldicarb, ethoprop, and phorate against indigenous nematode populations. Aldicarb consistently increased the number of millable stalks, cane tonnage, and yield of sucrose in soils with a high sand content. Yield increases were concomitant with reductions in the density of the nematode community shortly after planting and at harvest. In soils with a higher clay content, the chemicals were less effective in controlling nematode populations and, as a result, yield increases were minimal.
PubMed: 19271000
DOI: No ID Found -
Journal of Nematology Oct 1991Ditylenchus dipsaci (Kühn) Filipjev is a serious pest of commercial daffodil (Narcissus sp.) in northern California. The control measures practiced by growers in recent...
Ditylenchus dipsaci (Kühn) Filipjev is a serious pest of commercial daffodil (Narcissus sp.) in northern California. The control measures practiced by growers in recent years are postharvest treatment of planting bulbs for 3 hours in a 1% solution of formalin at 44 C combined with preplant soil fumigation with 1,3-dicbloropropene and (or) at-planting applications of phorate. In field trials, several combinations of rates (1.12, 2.24, or 4.48 kg a.i./ha in 189 liters of water/ha) and timings (one, two, or three applications at weekly intervals) of foliar applications with oxamyl on three daffodil varieties (Fortune, Ice Folley, and King Alfred) were evaluated as alternatives. Several treatments reduced nematode levels in leaves and bulbs. Phytotoxicity was not observed at any rate or combination of treatments.
PubMed: 19283189
DOI: No ID Found -
The Canadian Veterinary Journal = La... Apr 1991From 1982 to 1989, inclusive, 20 poisonings were investigated by the Ontario Ministry of Agriculture and Food following ingestion by domestic livestock of granular...
From 1982 to 1989, inclusive, 20 poisonings were investigated by the Ontario Ministry of Agriculture and Food following ingestion by domestic livestock of granular insecticides including terbufos (13 poisonings), disulfoton (two poisonings), fonofos (two poisonings), phorate (two poisonings), and carbofuran (one poisoning); all are used for rootworm (Diabrotica spp.) control in corn. A further three poisonings of livestock occurred following the ingestion of the foliar insecticide, endosulfan (two poisonings), and the seed protectant insecticides diazinon plus lindane (one poisoning). There were six poisoning cases as a result of excessive topical applications of the three insecticides coumpahos, fenthion, and lindane as dusts or sprays to control external parasites. Together, these events caused the deaths of 258 domestic animals of which 200 were cattle, 23 were swine, and 35 were sheep. Not all deaths are reported to the Ministry and the cases reported here may only represent 30-50% of the actual deaths over the period. Based on total populations of livestock, the percent losses were very small but they represent serious losses to individual growers. The economic loss is estimated at $160,000 over the eight years, or $20,000 per annum, and this does not include veterinary costs.Some of the poisoned animals died within as little as three to four hours of ingestion while others were sick but survived for several days. Lethal doses of insecticide were found in the rumen, abomasum, or stomach of dead animals. Signs typical of cholinesterase inhibition caused by organophosphorus poisoning were observed in most cases. Cholinesterase readings were found to be zero in dying animals. Necropsy findings were rarely more than pulmonary edema or myocardial hemorrhage. Where organochlorine insecticides were ingested, convulsions were the major manifestation.Contamination of feed was most often accidental, and chemical analysis was most helpful in identifying both potent and minor sources, thus facilitating cleanup procedures.
PubMed: 17423767
DOI: No ID Found -
Journal of Nematology Oct 1990Field experiments were conducted to evaluate the efficacy of five nematicides for the management of Rotylenchulus reniformis and for their effects on growth,...
Field experiments were conducted to evaluate the efficacy of five nematicides for the management of Rotylenchulus reniformis and for their effects on growth, development, and yield of cotton. Treatments included 1,3-dichloropropene (1,3-D), fenamiphos, phorate, terbufos, aldicarb, and 1,3-D + aldicarb. Average R. reniformis population densities across all treatments increased from 5,284 at 10 days after planting to a final density at harvest of 15,622 nematodes/500 cm(3) soil. The 1,3-D + aldicarb combination was the only treatment with an average R. reniformis population density significantly (P = 0.05) lower than that of the untreated control. Seedling stand at 28 days after planting was significantly less in aldicarb-treated plots than in control plots. Plant height was significantly greater in plots treated with nematicides than in the controls. Seed cotton yield was significantly greater from treated plots. Cotton plots treated with the 1,3-D + aldicarb combination produced the highest average yield of 4,139 kg/ha.
PubMed: 19287784
DOI: No ID Found -
Journal of Nematology Jan 1981The herbicides alachlor, linuron, vernolate, and metribuzin were applied to plots treated with the nematicide fensulfothion or the insecticide phorate and planted to...
The herbicides alachlor, linuron, vernolate, and metribuzin were applied to plots treated with the nematicide fensulfothion or the insecticide phorate and planted to soybean in two locations in North Carolina. In 1976 treatment with fensulfothion + alachlor or vernolate, phorate + alachlor or metribuzin resulted in greater nematode population densities than no treatment, or treatment with fensulfothion alone, or phorate alone. In 1977 fensulfothion and phorate alone and in combination with the preemergence herbicides effectively controlled Tylenchorhynchus cIaytoni. Late season population resurgence of Heterodera glycines occurred in fensulfothion + alachlor treated plots. Correlation coefficients for H. glycines vs. yield were -0.48 (P = 0.05) and -0.46 (P = 0.05) for 30 and 68 d after planting, respectively.
PubMed: 19300719
DOI: No ID Found -
The Canadian Veterinary Journal = La... Feb 1975
Topics: Animals; Cattle; Cattle Diseases; Female; Insecticides; Phorate
PubMed: 1131787
DOI: No ID Found -
The effect of the organophosphate O,O diethyl S-((ethylthio)methyl) phosphorodithioate on the chick.Poultry Science Mar 1972
Topics: Abnormalities, Drug-Induced; Animals; Brain; Chick Embryo; Chickens; Cholinesterases; Eggs; Insecticides; Iodine; Organ Size; Phorate; Poultry Diseases; Thyroid Gland
PubMed: 4643131
DOI: 10.3382/ps.0510613