Assessment of Azinphosmethyl Exposure in California Peach Harvest Workers

Abstract

We compared measurements of urinary alkylphosphate metabolites and oxime-induced reactivation of plasma cholinesterase (P-ChE) and erythrocyte acetylcholinesterase (RBC-AChE) with measurements of foliar residues, skin and clothing contamination, and P-ChE and RBC-AChE activities among 20 Northern California peach orchard workers exposed to the organophosphate agent azinphosmethyl (Guthion). Subjects entered orchards treated 30 d previously with azinphosmethyl and worked 21 d in treated fields during the ensuing 6 wk. Dislodgeable foliar residues ranged from 0.32-0.96 micrograms/cm2. Median reduction in RBC-AChE activity was 7% (p < .001) over the initial 3-d period of exposure and 19% (p < .01) over the 6-wk season. Urinary metabolites were the most sensitive indicator of recent exposure and correlated moderately with dermal and clothing levels (rs = +0.31-(+)0.55); urinary metabolites correlated well with RBC-AChE drawn 3 d after exposure began (rs = -0.77). No significant oxime-induced reactivation was found.

Agricultural task and exposure to organophosphate pesticides among farmworkers.

“…The previous studies we cited (Fenske et al 1999;Karr et al 1992;Loewenherz et al 1997;McCurdy et al 1994;Simcox et al 1999) have generally been convenience samples or samples obtained from a small selection of farms (where workplace norms may confer greater protection), or the samples may have been limited to certain farm tasks (such as mixing, loading, or applying pesticides) and it is not possible to determine whether the samples represent the larger population of workers within the same region. The strength of this study is the large study sample and the recruitment of both fieldworkers and pesticide mixers, loaders, and applicators.…”

“…Because many fieldworkers work on several crops, they may be exposed to several different types of pesticides throughout a given growing season. A limited number of previous investigations have examined workplace protective practices of this group (such as the frequency of use of gloves, long-sleeve shirts, and long pants) (Jackson 2002;Vela-Acosta et al 2002); only a limited number have assessed pesticide exposure among this group (Fenske et al 1999;McCurdy et al 1994;Simcox et al 1999).…”

Nondietary ingestion of pesticides by children in an agricultural community on the US/Mexico border: Preliminary results

“…Urine samples have been used to examine exposure to a suite of pesticides, through measurement of pesticides or their metabolites (Griffith and Duncan, 1985;McCurdy et al, 1994;Hill et al, 1995;Fenske et al, 2000;O'Rourke et al, 2000 ). In the most recent NHANES III report, 82% of individuals had measurable (>1 g/l) trichloropyridinal ( TCPY ), the primary metabolite of chlorpyrifos, in their urine ( Hill et al, 1995 ).…”

“…In the most recent NHANES III report, 82% of individuals had measurable (>1 g/l) trichloropyridinal ( TCPY ), the primary metabolite of chlorpyrifos, in their urine ( Hill et al, 1995 ). Urinary pesticide metabolites have been found to correlate well with erythrocyte acetylcholinesterase ( McCurdy et al, 1994 ). However, elevated levels of pesticide metabolites have been found in urine following organophosphate ( OP ) pesticide exposure, even when cholinesterase inhibition was not found in blood serum (Richter et al, 1992 ).…”

Identifying Constituents to Participate in a Project to Control Pesticide Exposure in Children of Farmworkers

“…Farmworkers also become part of a "takehome" pathway where pesticides and their residues are brought home on clothing (10)(11)(12) and skin (13,14) to children living in the house. Epidemiologic studies suggest that children exposed to pesticides have higher risks of childhood cancers (15)(16)(17)(18)(19)(20)(21), possible neurobehavioral effects (22,23), congenital malformations (24,25), and other health risks (26)(27)(28).…”