Residual metal soil contamination and associated health risks in a native American community within a remediated Superfund site in New Jersey, USA

Abstract This study evaluated whether remediation at the Ringwood Mines/Landfill Superfund site in New Jersey reduced soil heavy metal exposure and associated health risks for the Ramapough Lunaape Turtle Clan, a Native American community whose traditional ties to the local land may increase exposure to legacy pollution. Soil heavy metal concentrations were measured in frequently visited areas in and around the Ringwood Superfund site, and evaluated against background levels using the geo-accumulation index (I geo ) and ecological risk index (E r ). I geo results signaled anthropogenic enrichment of antimony, arsenic, cadmium, and lead, with cadmium showing E r values denoting very high ecological risks. Receptor models (Positive Matrix Factorization [PMF] and UNMIX) identified source profiles consistent with iron mine tailings (arsenic, cobalt, iron, and vanadium) and automotive waste (cadmium, chromium, lead, and nickel), linking observed contamination to the sources responsible for the site’s Superfund designation. Monte Carlo simulations of the hazard index (HI) and total cancer risk (TCR) indicated potential non-cancer and cancer risks for children and adults, primarily through soil ingestion, dermal contact, and game meat consumption—an oft-overlooked pathway in conventional risk assessments. Despite claims that the site is under control for human exposure, soil contamination from legacy sources persisted at levels associated with excess health risks. Findings from this study highlighted potential deficiencies in current remediation strategies in protecting the health of Native American communities with cultural and subsistence ties to their land, and contributed evidence that can inform future studies in similar settings.