Evaluation of Data Quality and Reliability for Chemical Hazard Assessment: A Case Study on Organic Photovoltaic Polymers

Chemical Hazard Assessment (CHA), which aims to investigate the inherent hazard potential of chemicals, has been developed with the purpose of promoting safer consumer products. Despite the increasing use of CHA in recent... [ view full abstract ]

Chemical Hazard Assessment (CHA), which aims to investigate the inherent hazard potential of chemicals, has been developed with the purpose of promoting safer consumer products. Despite the increasing use of CHA in recent years, there still remain problems such as data gap and data quality issues. The purpose of this study was to evaluate how data gaps and data reliability affect the assessment result. A case study approach was used, in which 142 low band gap polymers (LBGPs) used in the manufacturing of organic photovoltaic (OPV) modules were assessed. The CHA method used for this study was GreenScreenÒ for Safer Chemicals, an open-access CHA framework that assigns chemicals into four benchmark scores (BMs: BM1- chemicals of high concern; BM2- use but search for safer alternatives; BM3- use but still opportunity for improvement; BM4- safer chemicals; and BMU- unspecified due to insufficient data) according to their identified level of hazard in 20 hazard traits, including human health hazard traits (Carcinogenicity (C), Mutagenicity & Genotoxicity (M), Reproductive Toxicity (R), Developmental Toxicity (D), Endocrine Activity (E), Acute Mammalian Toxicity (AT), Systematic Toxicity & Organ Effects (ST-single), Neurotoxicity (N-single), Skin Irritation (IrS), Eye Irritation (IrE), Systematic Toxicity & Organ Effects* Repeated Exposure sub-endpoint (ST-repeated), Neurotoxicity- Repeated Exposure sub-endpoint (N-repeated), Skin Sensitization (SnS), Respiratory Sensitization (SnR)), physical hazard traits (Reactivity (Rx) and Flammability (F)), ecotoxicity traits (Acute Aquatic Toxicity (AA) and Chronic Aquatic Toxicity (CA), and environmental fate characteristics (Persistence (P) and Bioaccumulation (B)). In this case study, seven data sources, including the Globally Harmonized System of Classification and Labeling in Japan (GHS- Japan), Sigma Aldrich material safety data sheets (MSDSs), GESTIS, California Proposition 65 (Prop 65), The Endocrine Disruption Exchange (TEDX), EPI-Suite^TM and VEGA were used to conduct the CHA. Through data quality and information evaluation, we were able to examine which data sources are best suited for the current CHA framework and a rank of preference (GHS-Japan, Sigma Aldrich MSDSs, GESTIS, Prop 65, TEDX, VEGA and EPI Suite^TM) was determined based on six classification criteria: reliability, adequacy, transparency, volume, accessibility and ease of use. Further analysis of data gaps and uncertainty demonstrated that the assigned benchmark score for a given chemical may change due to the data reliability, and that BM1 scores were associated with the highest uncertainty. The results of this study highlight the importance of data source evaluation in CHA and revealed the need for more abundant and reliable hazard trait data.