Determinants of Skin and Respiratory Exposure to Lufenuron During Spraying and Re-entry in Italian Ornamental Plants Greenhouses.

The aim of this study was to evaluate dermal and respiratory exposure of workers to Lufenuron during spraying and re-entry on ornamental plants (stapling) in greenhouses. Potential and real skin exposure were evaluated using filter paper pads, hand contamination by washing, and respiratory exposure by personal air sampling. Dislodgeable foliar residues (DFRs) during re-entry were determined in order to calculate the dermal transfer factor (DTF). Lufenuron was analysed by liquid chromatography-mass detection. Respiratory dose (ReD) was calculated on the basis of a lung ventilation of 15-20 l min-1 and absorbed doses assuming a skin penetration of 13% and a respiratory retention of 100%. During stapling, from the dependence of exposure of hands from DFRs, the mean DTF was 0.575 cm2 h-1 (geometric mean). The ReD was 68.7-74.6 and 0.022-0.636% of the total real dose during spraying and stapling, respectively. The absorbed doses, 0.144-0.171 and 0.005-0.124 µg kg bw-1 during spraying and stapling, respectively, were less than the acceptable operator exposure level of 10 µg kg bw-1. Proper use of equipment and personal protective equipment and personal hygiene are aspects of fundamental importance on which workers must be trained. Adequate occupational hygiene studies are needed to support and verify working practices.

Creation of a database of occupational and environmental concentrations of crystalline silica dust for the purpose of assessing past and current exposures.

BACKGROUND: Professional exposure to respirable dust containing crystalline silica is of great interest for the serious lung diseases resulting from exposure. METHODS: During the period 1986-2019, 3611 exposure data to crystalline silica were collected from companies in central Italy. The data were divided and statistically analyzed based on the sampling system (Cyclone Dorr Oliver, CIP 10-R, Cyclone GS3, SKC plastic selector, Cyclone Higgins-Dewell and Cyclone Lippmann) and the ATECO code (code of economic activity, Italian acronym, used to classify companies when they interface with public institutions) of the companies in which they were collected. For each ATECO code, the division was made according to the type of sampling (personal or static) and the descriptive statistics of the data were calculated. RESULTS: Overall, for personal samples, 8.8% of the data exceeds 0.1 mg/m3, 19.6% exceeds 0.05 mg/m3 and 33.8% exceeds 0.025 mg/m3, the limit values set by the EU Directive 2019/130, suggested by the SCOEL and published by ACGIH respectively. The ATECO codes with the highest worker exposure (geometric means 0.067 and 0.069 mg/m3) were 23.31.00 (manufacture of ceramic tiles for floors and walls) and 23.42.00 (manufacture of ceramic sanitary ware), while the lowest exposure is found in 81.29.91 (cleaning and washing of public areas, removal of snow and ice including shedding of sand) with a geometric mean of 0.002 mg/m3. DISCUSSION: Despite the general reduction over time, there are still many sectors in which data are higher than the current occupational exposure limits; especially in these sectors it is necessary to implement the measures to fully assess worker exposure.

Evaluation of inhaled and cutaneous doses of imidacloprid during stapling ornamental plants in tunnels or greenhouses.

The aim of this research was to assess dermal and respiratory exposure of workers to imidacloprid during manual operations with ornamental plants previously treated in greenhouses or tunnels. A total of 10 female workers, 5 in greenhouses and 5 in tunnels, were monitored for 3 or 5 consecutive days. Actual skin contamination, excluding hands, was evaluated using nine filter paper pads placed directly on the skin. To evaluate the efficacy of protective clothing in reducing occupational exposure we also placed four pads on top of the outer clothing. Hand contamination was evaluated by washing with 95% ethanol. Respiratory exposure was evaluated by personal air sampling. Respiratory dose was calculated on the basis of a lung ventilation of 15 l/min. Absorbed doses were calculated assuming a skin penetration of 10% and a respiratory retention of 100%. Dislodgeable foliar residues (DFRs) were determined during the days of re-entry in order to determine the dermal transfer factor. From the dependence of dermal exposure of hands from DFRs, a mean transfer factor was estimated to be 36.4 cm(2)/h. Imidacloprid was determined by liquid chromatography with selective mass detection and electrospray interface in all matrices analysed. Respiratory dose was 4.1+/-4.0 (0.1-14.3)% and 3.0+/-2.0 (0.6-6.9)% (mean+/-SD (range)) of the total real dose during work in tunnels and greenhouses, respectively. The estimated absorbed doses, 0.29+/-0.45 microg/kg (0.06-2.25 microg/kg) body weight and 0.32+/-0.18 microg/kg (0.07-0.66 microg/kg) body weight (mean+/-SD (range)) in tunnels and in greenhouses, respectively, were less than the acceptable operator exposure level of 0.15 mg/kg body weight and than the acceptable daily intake of 0.05 mg/kg body weight. The hands and exposed skin of all workers were found to be contaminated, indicating that greater precautions, such as daily changing of gloves and clothing, are necessary to reduce skin exposure.

Evaluation of respiratory and cutaneous doses of chlorothalonil during re-entry in greenhouses.

Five female workers were monitored for 5 consecutive days during re-entry into a greenhouse containing ornamental plants. Skin contamination (excluding hands) was evaluated with nine pads of filter paper placed on the skin. Hand contamination was assessed by washing with 95% ethanol. Respiratory exposure was evaluated by personal air sampling. The respiratory dose was based on a lung ventilation of 15 l/min. The doses absorbed were estimated assuming 10% skin absorption and 100% lung retention. Dislodgeable foliar residue was determined on days of re-entry to evaluate the decay of chlorothalonil. Chlorothalonil was analysed in the different matrices by GC-MS. Respiratory exposure was less than skin contamination, being 11.4+/-5.1% (mean+/-SD) of total exposure. The estimated total absorbed dose did not exceed the acceptable daily intake of 0.03 mg/kg body mass. The hands and unexposed skin of all workers were always found to be contaminated. Greater precautions are therefore needed to reduce skin exposure (clean gloves and suitable clean clothing every day).