Pesticides Exposure by Air in Vineyard Rural Area and Respiratory Health in Children: A pilot study.

RATIONALE: Asthma, frequently associated with rhinitis, is the most common chronic disease in children, and a significant role is played by a range of environmental exposures. Among them, air pollution is of foremost concern. However, little is known about the impact of airborne pesticide exposure on children's respiratory health in rural areas. The objective of this study was to analyze the association between airborne pesticide exposure and asthma and rhinitis in children. METHODS: In a French vineyard rural area, children (3-10 years old) from 4 selected schools were invited to participate in this study over two periods: winter, with no or low air pesticide levels, and summer when fields are frequently treated with pesticides. Two health outcomes were considered: asthma and rhinitis symptoms (ISAAC questionnaire), and peak expiratory flow (PEF). A quantitative score of symptoms was built. Exposure to pesticides was evaluated 1) by measuring 56 pesticides in the ambient outdoor air around schools in the two periods and building a cumulative exposure index, and 2) by measuring ethylenethiourea (ETU) concentrations in urine in a subsample of children (n = 96), ETU being a urine biomarker of exposure to dithiocarbamates fungicides. Next, the association between pesticide exposure and respiratory health was studied using a logistic regression model, adjusted for confounders and respiratory status at baseline. RESULTS: 281 children participated in the study (47% girls, mean age: 7.5 yrs). 25% of the children were living on a farm. 22% had experienced wheezing at least once. 15.8% had asthma diagnosed by a doctor, 12% had current asthma and 35% had allergic rhinitis. The main pesticides detected in the ambient outdoor air around schools were fungicides (89,3%; mainly folpet and dithiocarbamates) and insecticides (10.6%). No association was found between the symptom score and pesticides in the outdoor air around schools during summer, when pesticides were applied to vineyards. However, an association was found between ETU urinary concentration (>0.974 µg/g creatinine) and asthma and rhinitis symptoms (OR=3.56; IC 95% 1.04-12.12). This result could be explained by extracurricular exposure, which was not considered in our air measurements in the schools. No association was found between peak expiratory flow and exposure to pesticides in the air. CONCLUSIONS: Children living in vineyard rural areas are at a higher risk of airborne dithiocarbamates exposure during the summer period. Despite the limited size of our sample, our results suggest possible links between some pesticide measurements and respiratory and allergic symptoms such as rhinitis.

Descriptive epidemiology and risk factors of primary central nervous system tumors: Current knowledge.

Although comparisons are difficult due to differences in methodologies, the annual incidence rates of central nervous system (CNS) tumors range from 8.5 to 21.4/100,000 population according to cancer registries, with a predominance of neuroepithelial tumors in men and meningiomas in women. An increase in the incidence of CNS tumors has been observed during the past decades in several countries. It has been suggested that this trend could be due to aging of the population, and improvements in diagnostic imaging and healthcare access, but these factors do not explain differences in incidence by gender and histological subtypes. Several etiological hypotheses related to intrinsic (sociodemographic, anthropometric, hormonal, immunological, genetic) and exogenous (ionizing radiation, electromagnetic fields, diet, infections, pesticides, drugs) risk factors have led to analytical epidemiological studies to establish relationships with CNS tumors. The only established environmental risk factor for CNS tumors is ionizing radiation exposure. However, for other risk factors, studies have been inconsistent and inconclusive due to systematic differences in study design and difficulties in accurately measuring exposures. Thus, the etiology of CNS tumors is complex and may involve several genetic and/or environmental factors that may act differently according to histological subtype.

Epidemiology of meningiomas.

Although they represent about a third of all the tumors of the central nervous system, knowledge concerning meningioma epidemiology (including incidence data and exploration of the risk factors) remains scarce compared to that of gliomas. A limited number of cancer registries worldwide only record malignant brain tumors, however their completeness and accuracy have been questioned. Even if comparisons are made difficult due to differences in methodologies, available annual incidence rates (sex- and age-standardized, generally on US or World standard population), provided by population-based registries range from 1.3/100,000 to 7.8/100,000 for cerebral meningiomas. An increase in the incidence of primary brain tumors in general and of meningiomas in particular has been observed during the past decades in several countries. It has been suggested that this trend could be artefactual and could be the resultant of an ageing population, improvement in health access and in diagnostic procedures, changes in coding classification for tumors recorded in registries, and/or an increase in the rate of histological confirmation, even in the elderly. All these factors are likely to play a role but they might not fully explain the increase in incidence, observed in most age groups. In addition to intrinsic risk factors (gender, ethnic groups, allergic conditions, familial and personal history, genetic polymorphisms), some exogenous risk factors have been suspected to play a role in the etiology of meningiomas and their changes with time is likely to impact incidence trends. A causal link has been established only for ionising radiation but the role of many other factors have been hypothesised: electromagnetic fields, nutrition, pesticides, hormonal as well as reproductive factors. Considering the serious or even lethal potentiality of some meningiomas and the apparent rise in their incidence, all practitioners involved in neuro-oncology should feel concerned today of the necessity to better assess their public health burden and to study their epidemiological features.

Descriptive epidemiology of CNS tumors in France: results from the Gironde Registry for the period 2000-2007.

An increase in the incidence of CNS tumors has been observed in many countries in the last decades. The reality of this trend has been much debated, as it has happened during a period when computer-assisted tomography and MRI have dramatically improved the detection of these tumors. The Gironde CNS Tumor Registry provides here the first data on CNS tumor incidence and trends in France for all histological types, including benign and malignant tumors, for the period 2000-2007. Incidence rates were calculated globally and for each histological subtype. For trends, a piecewise log-linear model was used. The overall annual incidence rate was found to be 17.6/100 000. Of this rate, 7.9/100 000 were neuroepithelial tumors and 6.0/100 000 were meningiomas. An overall increase in CNS tumor incidence was observed from 2000 to 2007, with an annual percent change (APC) of +2.33%, which was explained mainly by an increase in the incidence of meningiomas over the 8-year period (APC = +5.4%), and also more recently by an increase in neuroepithelial tumors (APC = +7.45% from 2003). The overall increase was more pronounced in women and in the elderly, with an APC peaking at +24.65% in subjects 85 and over. The increase in the incidence rates we observed may have several explanations: not only improvements in registration, diagnosis, and clinical practice, but also changes in potential risk factors.