Urban soils can accumulate metal(loid)s from past and current human activities, yet data from mid-sized U.S. cities remain limited. The study aims to comprehensively map and analyze soil contamination, understand its socioeconomic impacts. The ultimate goal is to equip the community with critical data to mitigate heavy metal exposure and inform future urban planning and public health policies. This dataset reports concentrations of As, Cr, Cu, Mn, Ni, Pb, and Zn measured in 1,290 composite topsoil samples (0–2.5 cm) from five land uses in Lafayette, Louisiana (USA). This study provides critical insights into the distribution of heavy metals in urban settings, emphasizing the need for preventative measures and targeted interventions to mitigate exposure risks. The comprehensive mapping and analysis of soil contamination in Lafayette, LA, serve as a model for addressing similar issues in other urban areas, contributing to the broader understanding of environmental justice and public health.

Between 2021 and 2023, we collected 1,290 composite topsoil samples from 24 selected census tracts within Lafayette, Louisiana (USA). The goal was to comprehensively map soil heavy metal(loid) contamination and understand its health and socioeconomic impacts. Samples were collected from both public and residential areas, including high-traffic roadways, industrial zones, parks, and residential regions near house foundations, street sides, open spaces, and gardens. Typically, one representative sample with five subsamples was collected. In residential areas, five samples were collected within one meter of house foundations, five within one meter of street sides, and five from open spaces. All samples were collected from the topsoil layer (0-2.5 cm depth), which is the primary zone of contact for children and the layer where heavy metals tend to accumulate. Collected soil samples were oven-dried for 24 hours at 105 degrees Celsius, ground, and sieved through a <2 mm sieve to ensure uniformity. Laboratory analysis was performed in the Delta Urban Soils Laboratory at the University of Louisiana at Lafayette, utilizing a handheld X-ray fluorescence (XRF) analyzer in a benchtop stand (Thermo Niton XL3t 955 Ultra). The detection limit of the instrument in the Standard Reference Material (SRM) matrix is 8 mg/kg, according to the manufacturer (Thermo Scientific, 2024). Measurements resulting in a reading of less than the limit of detection were substituted with 8 mg/kg for statistical purposes. The soil samples were analyzed in low-density polyethylene bags using the XRF for 90 seconds each. Each batch included testing SRM reference standards. Results from the XRF analysis for soils were compared to U.S. National Institute of Standards and Technology (NIST) Standard Reference Materials (SRM) soils: SRM 2710a, SRM 2711a, SRM 2704, and SRM 2709a. The readings were not adjusted. In the dataset, elemental concentrations are reported by census tract to ensure the privacy and confidentiality of individual site owners. Values of 0 in the columns represent measurements below the detection limit of the XRF instrument.