Relationship between the paraoxonase 1 (PON1) M55L and Q192R polymorphisms and lymphohaematopoietic cancers in a Greek agricultural population.

The aim of this study was to investigate the association between Paraoxonase 1 (PON1) gene polymorphisms (M55L and Q192R) and lymphohaematopoietic cancers (LHC) in an agricultural region of Greece. A hospital-based case-control study was conducted. A structured questionnaire including information on demographics, residence, occupation, agricultural practices, pesticide exposure, family history, smoking, alcohol consumption and medical history, was used. Genotyping of 316 cases of LHC and 351 healthy controls by using standard laboratory methods was performed. To control for confounders, Binary and Multinomial Logistic Regression analyses were used. Possession of QQ genotype or presence of the Q allele were associated with increased risk of developing LHC (OR 1.94, 95% CI 1.42-2.66 and OR 1.72, 95% CI 1.33-2.23 respectively). The QQ genotype in the recessive model was independently associated with LHC (OR 1.92, 95% CI 1.40-2.65), leukaemia (OR 1.99, 95% CI 1.13-3.49), lymphoma (OR 2.17, 95% CI 1.21-3.90) and plasmacell disease (OR 1.92, 95% CI 1.40-2.65) even after controlling for age, sex, pesticide exposure, smoking and family history (cancers, LHC and immunological disorders) as confounders. Possession of QQ genotype was found to have a stronger association with LHC in the high and medium pesticide exposed groups(OR 2.15, 95% CI 1.35-3.40, P-value 0.001 and OR 2.25, 95% CI 1.21-4.19, P-value 0.010 respectively), compared with the Low/No exposed group where the association was not statistically significant (OR 1.51, 95% CI 0.76-3.00, P-value 0.224). We found no association between M55L polymorphism and LHC. PON1 polymorphisms may influence the risk for LHC in our agricultural area. The results encourage further investigation on the PON1 polymorphisms and their importance on the individual's susceptibility especially when exposure to pesticides occurs.

Pesticide exposure and lymphohaematopoietic cancers: a case-control study in an agricultural region (Larissa, Thessaly, Greece).

BACKGROUND: The causality of lymphohaematopoietic cancers (LHC) is multifactorial and studies investigating the association between chemical exposure and LHC have produced variable results. The aim of this study was to investigate the relationships between exposure to pesticides and LHC in an agricultural region of Greece. METHODS: A structured questionnaire was employed in a hospital-based case control study to gather information on demographics, occupation, exposure to pesticides, agricultural practices, family and medical history and smoking. To control for confounders, backward conditional and multinomial logistic regression analyses were used. To assess the dose-response relationship between exposure and disease, the chi-square test for trend was used. RESULTS: Three hundred and fifty-four (354) histologically confirmed LHC cases diagnosed from 2004 to 2006 and 455 sex- and age-matched controls were included in the study. Pesticide exposure was associated with total LHC cases (OR 1.46, 95% CI 1.05-2.04), myelodysplastic syndrome (MDS) (OR 1.87, 95% CI 1.00-3.51) and leukaemia (OR 2.14, 95% CI 1.09-4.20). A dose-response pattern was observed for total LHC cases (P = 0.004), MDS (P = 0.024) and leukaemia (P = 0.002). Pesticide exposure was independently associated with total LHC cases (OR 1.41, 95% CI 1.00 - 2.00) and leukaemia (OR 2.05, 95% CI 1.02-4.12) after controlling for age, smoking and family history (cancers, LHC and immunological disorders). Smoking during application of pesticides was strongly associated with total LHC cases (OR 3.29, 95% CI 1.81-5.98), MDS (OR 3.67, 95% CI 1.18-12.11), leukaemia (OR 10.15, 95% CI 2.15-65.69) and lymphoma (OR 2.72, 95% CI 1.02-8.00). This association was even stronger for total LHC cases (OR 18.18, 95% CI 2.38-381.17) when eating simultaneously with pesticide application. CONCLUSIONS: Lymphohaematopoietic cancers were associated with pesticide exposure after controlling for confounders. Smoking and eating during pesticide application were identified as modifying factors increasing the risk for LHC. The poor pesticide work practices identified during this study underline the need for educational campaigns for farmers.