Evaluation of Stoffenmanager and a New Exposure Model for Estimating Occupational Exposure to Styrene in the Fiberglass Reinforced Plastics Lamination Process

Abstract

This study aims to evaluate occupational exposure models by comparing model estimations of Stoffenmanager, version 8.2, and exposure scores calculated using a new exposure model with personal exposure measurements for styrene used in the fiberglass-reinforced plastic (FRP) lamination processes in Korea. Using the collected exposure measurements (n = 160) with detailed contextual information about the type of process, working conditions, local exhaust ventilation, respiratory protections, and task descriptions, we developed a new model algorithm to estimate the score for occupational exposures on situation level. We assumed that the source of exposure originates from the near field only (within the breathing zone of workers). The new model is designed as a simple formula of multiplying scores for job classification, exposure potential, engineering controls, chemical hazard, and exposure probability and then dividing the score for workplace size. The final score is log-transformed, ranging from 1 to 14, and the exposure category is divided into four ratings: no exposure (1), low (2), medium (3), and high (4) exposures. Using the contextual information, all the parameters and modifying factors are similarly entered into the two models through direct translation and coding processes with expert judgement, and the exposure estimations and scores using the two models are calculated for each situation. Overall bias and precision for Stoffenmanager are −1.00 ± 2.07 (50th) and −0.32 ± 2.32 (90th) for all situations (n = 36), indicating that Stoffenmanager slightly underestimated styrene exposures. Pearson’s correlation coefficients are significantly high for Stoffenmanager (r = 0.87) and the new model (r = 0.88), and the correlation between the two models is significantly high (r = 0.93) (p < 0.01). Therefore, the model estimations using Stoffenmanager and the new model are significantly correlated with the styrene exposures in the FRP lamination process. Further studies are needed to validate and calibrate the models using a larger number of exposure measurements for various substances in the future.

Evaluating the Theoretical Background of STOFFENMANAGER® and the Advanced REACH Tool

“…This showed that the multipliers do not explain the exposure very well ( Savic et al , 2017a ). Residual analysis shows that STOFFENMANAGER ® and ART have a systematic tendency to overestimate low exposures and underestimate high exposures ( Mc Donnell et al , 2011 ; Landberg et al , 2017 ; Savic et al , 2017a ; Lee et al, 2019a , b , 2020 ). The reason for this trend is not known.…”

“…The models fail to estimate reasonable worst-case exposure estimates usually by two or more orders of magnitude. Because of this high uncertainty, the exposure is often underestimated in over 10% of the predicted exposures even when using the upper level of the 90 or 95% confidence interval of the 90th or 95th percentile ( Landberg et al, 2015 , 2017 ; Riedmann et al , 2015 ; Savic et al , 2017a ; van Tongeren et al , 2017 ; Lee et al, 2019a , b , 2020 ). The STOFFENMANAGER ® evaluation report by Dutch Ministry of Social Affairs and Employment is not accessible according to personal communication with Cosanta, ECHA, The Finnish Safety and Chemicals Agency, and Rijksoverheid (the Netherlands).…”

Possibility of Benzene Exposure in Workers of a Semiconductor Industry Based on the Patent Resources, 1990–2010

“…To more objectively assess the possibility of benzene exposure, a scoring system using exposure-related parameters was used. The scoring technique is used to qualitatively or semiquantitatively evaluate the hazard and exposure of chemicals [ [24] , [25] , [26] ]. All 22 patent documents that recorded the use of benzene were evaluated with more than 6 points ( Table 2 ).…”

Modelling Exposure by Spraying Activities—Status and Future Needs

“…For Stoffenmanager ® , 11 studies were evaluated (see Table S3) in which spraying activities were included. A main conclusion of most studies is that Stoffenmanager ® is a balanced model with a medium level of conservatism, when considering the 90th percentile [58,78,79]. The few studies that examined the 50th percentile came to a similar conclusion.…”