32P-Postlabeling Detection of DNA Adducts in Peripheral White Blood Cells of Greenhouse Floriculturists from Western Liguria,

Pesticides are widely used in agriculture to enhance crop yields and to control disease vectors. Floriculturists work frequently in greenhouses and may be exposed to high levels of pesticides, which may result in adverse health effects. To evaluate the relationship between exposure to pesticides and DNA adduct formation in peripheral WBCs of Italian floriculturists, the nuclease P1 modification of a 32P-postlabeling assay was used to analyze WBC DNA from floriculturists (n = 26) and matched controls (n 22). DNA adduct-positive samples were more frequent in floriculturists (11126; 42%) than in matched controls (2/22; 9%) (P < 0.01). Slightly higher frequencies of DNA adduct-positive samples were observed in floriculturists 44 years of age (53%) and in female floriculturists (57%). Floricultural practice was found to be associated with a significantly higher DNA adduct-positive rate in WBCs (rate ratio, 5.12; 95% confidence interval, 1.1-23.7) after allowing for the effects of age and gender. These two latter covariates were not significantly associated with DNA adduct-positive rates. The quantitative levels of DNA adducts were significantly higher in floriculturists than in matched controls according to the Mann-Whitney nonparametric statistic (P = 0.0052). The median adduct level for positive samples among floriculturists was 1.5/108 bases. A specific, well-visible spot, named a adduct, was detected in 7 out of the 1 1 DNA adduct-positive samples from floriculturists but in none of the (22 + 20) referent samples (P = 0.0004). The presence of pesticide-related DNA adducts was confirmed clearly using the butanol extraction procedure. Six of 8 floriculturists and 0 of 10 Received 5/30/95; revised 1/5/96; accepted 1/26/96. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked adrertise,ne,tt in accordance with 18 U.S.C. Section 1734 solely to indicate this fact. I This work was supported partially by Consiglio Nazionale delle Ricerche targeted project Prevention and Control of Disease Factors. Consiglio Nazionale delle Richerche project Applicazioni Cliniche della Ricerca Oncologica (sub-pr. I and 2). a Finalized Project of Ministry of Health, European Community Environmental Research Programme Contract #91-01 61. and Associazione Italiana per Ia Ricerca sul Cancro (AIRC 1995). 2 To whom requests kr reprints should be addressed, at Istituto Nazionale per Ia Ricerca sul Cancro. Laboratory of Experimental Oncology. Viale Benedetto. XV. n.l0. 16132 Genova. Italy. referents were found positive with this method. The median adduct level for positive samples was 6.0/10 bases. Two strong spots close to the origin could be identified in all six positive floriculturists, using the butanol extraction procedure. No association between DNA adducts and use of specific pesticides was observed.