Agathi Charistou

EVALUATION OF POTENTIAL DERMAL EXPOSURE OF PESTICIDE SPRAY OPERATORS IN GREENHOUSES BY USE OF VISIBLE TRACERS

In the present study, the potential dermal and inhalation exposure of the operator was measured, following simulation of insecticide application with the dye tracer Sunset Yellow in greenhouse cucumbers and tomatoes. For the monitoring of operator exposure, the whole body technique was used. The potential inhalation exposure was measured with a personal air sampler equipped with a glass fiber filter. The potential dermal operator exposure ranged from 84.4 to 526.7 ml of spray solution (s.s.)/h for the whole body and from 18.5 to 62.5 ml s.s./h for hands in the case of greenhouse cucumbers. The respective inhalation exposure was between 0.17 and 1.0 ml s.s./h. For greenhouse tomatoes, the potential body exposure was in the range of 22.4 to 62.1 ml s.s./h. The hand exposure varied from 5.5 to 6.1 ml s.s./h. The potential inhalation exposure was in the range of 0.33 to 0.43 ml s.s./h. The potential dermal operator exposure is a highly variable parameter, with a variation factor higher than 100% in many cases. One of the most critical factors for the determination of both potential dermal and inhalation exposure is the application pressure. Other field and operational conditions, including unpredictable factors, are also important for the determination of operator exposure levels. The measured potential dermal operator exposure values were above the levels of exposure estimated with mathematical models.

Dermal Exposure of Pesticide Applicators as a Measure of Coverall Performance Under Field Conditions

In this study, the field performance of two coverall designs used by pesticide applicators was determined. Two coverall types were selected based on data from previously conducted comfort testing under field conditions in southern Europe. Dermal exposure was measured during 22 applications conducted with 11 operators using similar hand-held spray guns in greenhouse pepper crops in the Ierapetra region of Crete, Greece. One of the coverall designs studied was made from a cotton/polyester material treated with a water-repellent Resist Spills(R) finish, which was compared in the field study to a coverall of similar design, but using a woven, untreated cotton material. An in-house analytical method was developed and validated for determining residues of the active substance (a.s.) malathion on the dosimeters. The derived levels of dermal exposure were used as a measure of the protection provided by the two types of coveralls. In addition, by comparing the total amount of the a.s. recovered from outer and inner dosimeters (potential dermal exposure = 238.8 mg kg(-1) a.s. for the cotton coverall and 160.44 mg kg(-1) a.s. for the Resist Spills coverall), a value could be determined for the degree of coverall penetration. The mean penetration (milligrams per kilogram a.s.) of the outer coveralls, calculated as a percentage of the total contamination, was 0.4% for the water-repellent coverall and 2.3% for the cotton coverall. The mean recovery from the laboratory and field-fortified samples was >91 and 74%, respectively and used as the main criterion for quality control of the analytical data. Under the field trial conditions evaluated, both the coverall designs gave better protection than the default values used in the most relevant predictive exposure model. Therefore, they could be considered as appropriate tools of personal protection when both comfort and field performance is taken into account under the specific application scenario.

Determination of operator exposure levels to insecticide during bait applications in olive trees: Study of coverall performance and duration of application

In this study the operator exposure levels during bait applications of an insecticide in olive groves were determined using a whole body dosimetry method for dermal exposure. The study design allowed the roles of application task duration and coverall type to be evaluated as factors influencing operator exposure. Twenty applications were carried out with knapsack sprayers in the Tanagra region of Viotia, Greece, ten of which were for a 1h and ten for a 3h duration. An in-house GC-NPD analytical method was developed and validated for the determination of malathion, the active substance (a.s.) of the insecticide formulation used in field trials. The mean recovery of field-fortified samples was 84% (%RSD=3.0). Field trial results generally indicated lower operator exposure levels than indicated by the most relevant operator exposure predictive model. Residues of malathion on internal dosimeters were compared to those measured on the respective outer coveralls (potential dermal exposure) to evaluate the protective factor of each one of the two coverall types used. Both coverall types provided satisfactory levels of protection and can be considered as suitable protection for the conditions of the application scenario studied. Furthermore, the results indicated that there is not a strong correlation between exposure levels and duration of application.

Perceptions of pesticides exposure risks by operators, workers, residents and bystanders in Greece, Italy and the UK

The EU Directive on the sustainable use of pesticides (EU128/2009/EC) requires European Member States to develop training activities targeting occupational exposure to pesticides, and communication material aimed at residents and bystanders. Risk perceptions, knowledge and attitudes associated with passive and occupational exposure to pesticide potentially influence the extent to which different stakeholders adopt self-protective behaviour. A methodology for assessing the link between attitudes, adoption of self-protective behaviours and exposure was developed and tested. A survey was implemented in the Greece, Italy and the UK, and targeted stakeholders associated with pesticide exposure linked to orchards, greenhouse crops and arable crops respectively. The results indicated that the adoption of protective measures is low for residents and bystanders, with the exception of residents in Greece, when compared to operators and workers, who tend to follow recommended safety practices. A regression analysis was used to examine the factors affecting the probability of adopting protective measures as well the as the level of exposure in the case of operators and workers where data are available. The results indicate that the likelihood of engaging in self-protective behaviour is not significantly affected by perceptions of own health being affected by pesticides for residents and bystanders. However, operators who perceive that their heath has been negatively affected by the use of pesticides are found to be more likely to adopt self-protective behaviours. Gender and country differences, in perceptions, attitudes and self-protection are also observed. Recommendations for improved communication, in particular for vulnerable groups, are provided.

Dermal & inhalation exposure of operators during fungicide application in vineyards. Evaluation of coverall performance.

In the present study the dermal and the inhalation exposure of five operators during fungicide applications in vineyards were determined. The produced exposure datasets can be used as surrogate for the estimation of the actual and the potential dermal as well as inhalation operator exposure levels for this application scenario. The dermal exposure was measured using the whole body dosimetry method while the inhalation exposure with the use of personal air sampling devices with XAD tubes located on the operators breathing zone. Ten field trials were carried out by 5 different operators using a tractor assisted hand-held lance with spray gun at the Tanagra region of Viotia, Greece. An in-house GC-ECD analytical method was developed and validated for the determination of penconazole, which was the active substance (a.s.) of the fungicide formulation used in field trials. The mean recovery of field-fortified samples was 81%. The operator exposure results showed expected variability and were compared to those derived from the German model for prediction of operator exposure. The comparison of the 75th percentile values for an operator wearing personal protection equipment has shown that the measured levels were 2.2 times lower than those estimated by the German model. The levels of actual dermal exposure ranged from 2 to 19 mg/kg a.s. applied. The protection provided by the two types of coveralls was evaluated and in comparison to the existing reduction factors used for other types of PPE (coveralls) was found satisfactory for the operator under the conditions of the specific applications.

Assessment of field re-entry exposure to pesticides: A dislodgeable foliar residue study

A dislodgeable foliar residue study was conducted in greenhouse pepper and tomato on the island of Crete, Greece, following the spray application of an SC insecticide (with active substance (a.s.) tebufenozide) and an EC fungicide (a.s. bupirimate). Furthermore, for the assessment of worker exposure to pesticides - as a result of re-entering the treated crops - a worker dermal exposure study was carried out during the tasks of tying or pruning, which allowed the transfer coefficient values for the specific tasks to be determined. Pesticide residues were analysed with an in house developed and fully validated HPLC-ESI/MS analytical method. The results from the study resulted in transfer coefficient values which were in agreement with current EFSA guideline values in most of the cases with the exception of bupirimate in a tomato greenhouse. In that case, high potential dermal exposure and low dislodgeable foliar residue values were observed, which is thought to be due to the moist leaves collected during sampling and monitoring, which led to greater than expected transfer coefficient values.

Determination of pesticide dermal transfer to operators and agricultural workers through contact with sprayed hard surfaces: Pesticide dermal transfer through contact with sprayed hard surfaces

BACKGROUND In the present study, the rate of dermal transfer of pesticides to agricultural workers occurring via contact with sprayed hard surfaces was investigated. Cotton gloves were used as dosimeters to collect residues from hard surfaces contaminated by pesticides in greenhouses. Dosimeters, either dry or moistened, were in contact with wood, metal and plastic surfaces that had previously been sprayed. The experimental approach applied mimicked typical hand contact. Moistened cotton gloves were used to simulate hand moisture from dew/condensation or rainfall. The effect of total duration of contact on the final hand exposure via transfer was investigated. RESULTS The higher duration contact tested (50 s) resulted in higher transfer rates for metal and plastic surfaces; no such effect was noted in the case of the wood surface. The pesticide amount transferred from the metal and plastic surfaces to wet gloves was greater than that transferred to dry gloves. Such a trend was not observed for the wood surface. Transfer rates varied from 0.46 to 77.62% and from 0.17 to 16.90% for wet and dry samples, respectively. CONCLUSION The current study has generated new data to quantify the proportion of pesticide deposits dislodged from three different non-crop surfaces when in contact with dry or wet gloves.