摘要:

To assess the impact of long‐term feeding of fungicides on sperm quality, mice were fed a daily diet containing a mixture of maneb and zineb, at concentrations of 30, 300, and 3000 ppm, respectively. Employing epididymal sperm suspended in a medium permitting in vitro capacitation, the intracellular free Ca2+concentration, [Ca2+]i, was determined with a fluorescent Ca2+indicator, Fura‐2. Regardless of the fungicide dosages applied, [Ca2+]i was about 50 percent higher in treated animals relative to a value of 123 nM [Ca2+]i in the control group. Fungicide‐treated mice were mated to mature, non‐treated females; as in the control, the litter sizes were the same. In conclusion, the observed elevation in [Ca2+]i seems to reflect cellular adaptation responses to toxic stress at moderate fungicide doses.

ISSN:0360-1234    

DOI:10.1080/03601239209372763

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Total body dose of 2,4‐D was determined in 10 volunteers following exposure to sprayed turf 1 hour following application and in 10 volunteers exposed 24 hours following application. Each group of 10 volunteers was divided in half and five wore long pants, a short‐sleeved shirt, socks and closed footwear. The other five wore shorts and a short‐sleeved shirt and were barefoot. All volunteers were exposed to a 2 by 15 m area of turf for 1 hour during which they alternated between walking and sitting or lying on the turf surface for intervals of 5 minutes. Dislodgeable residues of 2,4‐D taken during the exposure sessions showed a rapid decline from 1 hour following application (8%) to 24 hours following application (1%). No detectable residues were found in 4‐day urine samples supplied by volunteers except for 3 people who were barefoot and wearing shorts and contacted the turf 1 hour following 2,4‐D application. The highest dose was measured in a volunteer who removed his shirt for 30 minutes of the exposure session (426μg). Exposure levels of the other two volunteers who wore the prescribed clothing were lower (153 and 103μg). No detectable residues were found in urine samples supplied by volunteers exposed to sprayed turf 24 hours following application. These results indicate that at the doses measured, exposure to sprayed turf should present little risk in humans. However, people can reduce exposure to non‐detectable levels by remaining off treated turf for a period of 24 hours or until after rainfall or irrigation so that dislodgeable residues and therefore potential exposure are essentially zero.

ISSN:0360-1234    

DOI:10.1080/03601239209372764

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Total body dose received in home gardeners applying 2,4‐D and bystanders living within the household, but not applying the pesticide was measured. Levels of 2,4‐D were monitored in air samples both inside the home and downwind of the application site. Homeowners were divided into protective and non‐protective apparel groups and applied both a granular and liquid formulation of 2,4‐D on two separate dates. Analyses of urine collected from homeowners for 96 hours following applications found total body doses ranging from non‐detectable to 0.0071 mg/kg of body weight. The highest exposures occurred in the non‐protected group and were consistently associated with spills of the liquid concentrate or excessive contact with the dilute mixture on the hands or forearms. Residues of 2,4‐D were not detected in urine samples supplied by bystanders to home applicators. Residues of 2,4‐D were detected in five of the 76 air samples taken during the home applications. ^Two of these air samples coincided with measurable applicator exposure but it is unlikely that this was a major route of exposure.

ISSN:0360-1234    

DOI:10.1080/03601239209372765

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

A method is presented for either simultaneous or separate residue analysis of 2,6‐dinitro‐N,N‐dipropyl‐4‐trifluoromethylaniline (trifluralin) and N‐butyl‐N‐ethyl‐2, 6‐dinitro‐4‐trifluoromethylaniline (benfluralin) in turfgrass thatch and soil. Trifluralin and/or benfluralin residues are extracted from thatch and soil with acetohitrile‐water mixture, reextracted and purified with C18solid‐phase extraction (SPE) tubes, and quantified by megabore column gas chromatography with a nitrogen specific detector. Method sensitivity for both compounds is 0.05 mg/kg for thatch and 0.02 mg/kg for soil.

ISSN:0360-1234    

DOI:10.1080/03601239209372766

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The biochemical response to controlled inhalation of nitrogen dioxide (NO2) was studied in 18 male guinea pigs. Animals were exposed to 2.5, 5.0, and 10 ppm NO2for 2h daily for 35 consecutive days, and the results compared with six control animals exposed to filtered air for 2h daily for same period. Five biochemical parameters, including triglyceride, free fatty acids, esterified fatty acid, ganglioside and lipase activity were measured immediately after the last day of exposure.

ISSN:0360-1234    

DOI:10.1080/03601239209372767

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

A bioassay method was developed to determine field deposits and persistence ofBacillus thuringiensisvar.kurstaki(B.t.k.) protein (in ng/g foliage, and ng/cm of foliar area), after aerial application of Foray®48B formulation over a hardwood forest. Two blocks (B1 and B2) were sprayed at 50 BIU in 3.94 L/ha. initial deposits and persistence of protein were assessed by two force‐feeding bioassay methods, foliar‐extract‐bioassay (FE‐bioassay) and redissolved‐protein‐bloassay (RP‐bioassay), using fourth instar gypsy moth (Lymantria disparL.) larvae.

ISSN:0360-1234    

DOI:10.1080/03601239209372768

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor