Mixture risk assessment of nine reproductive toxic chemicals affecting male sperm quality in a representative sample of children and adolescents living in Germany – results from the German Environmental Survey (GerES V)

Reproductive health is declining globally, with growing evidence linking exposure to endocrine-disrupting chemicals during critical pregnancy stages to adverse male sexual development. This study assessed the cumulative risk of nine such chemicals—acrylamide, PCB 118, DEHP, DnBP, DiBP, BBzP, DiNP, DCHP, and DnPeP—and possible influencing factors such as age, socioeconomic status (SES), and region (former East vs. West Germany). We analyzed cross-sectional data from the German Environmental Survey for Children and Adolescents 2014–2017 (GerES V), including 1090 participants with complete urine and plasma samples. Using the Hazard Index (HI) method, which combines exposure levels with human biomonitoring guidance values, we found that 31% of participants had an HI above 1, indicating elevated risk from combined chemical exposure. Notably, 26% of these cases would have gone unnoticed in single-substance assessments. DnBP, DiBP, and acrylamide were the main contributors to overall risk. Stratified analyses revealed that younger children had higher HI levels than older ones. Children from lower SES backgrounds also showed higher risk compared to those from medium or high SES groups. Additionally, residing in former East Germany was associated with increased HI levels compared to former West Germany. These findings emphasize the importance of considering chemical mixtures in risk assessments and recognizing subgroup-specific vulnerabilities. Future assessments should expand the range of included chemicals and focus on high-risk groups—especially children, individuals with low SES, and residents of former East Germany—to better capture the scope of potential health impacts. • Mixture risk assessment (MRA) of 9 substances impairing reproduction using HBM-GV. • MRA in a population-representative sample of children and adolescents. • 31% exceed Hazard Index of 1. • 26% of HI > 1 would have gone unnoticed in single-substance risk assessment. • Higher cumulative exposure in young children, low SES, and former East Germany.