Evaluating the Portable X-ray Fluorescence Reliability for Metal(loid)s Detection and Soil Contamination Status
Aug. 27, 2024
Zain Alqattan, NIEHS Superfund Research Program Trainee and PhD candidate working under Dr. Ramirez-Andreotta’s mentorship, recently published “Evaluating the Portable X-ray Fluorescence Reliability for Metal(loid)s Detection and Soil Contamination Status.”
The study makes evident how marginalized communities experience barriers that can prevent soil monitoring efforts and knowledge transfer. To address this challenge, this study compared two analytical methods: portable X-ray Fluorescence Spectroscopy (pXRF) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The pXRF method requires less time and has a lower cost, while ICP-MS is the “gold standard.”
Surface soil samples were collected from residential sites in Arizona and public areas in Troy, New York. Soil preparation differed between groups to account for community practice. Statistical calculations were conducted: paired t-test, Bland-Altman plot, and a two-way ANOVA indicated no significant difference for arsenic, barium, calcium, copper, manganese, lead, and zinc concentrations except for barium in the t-test. Iron, nickel, chromium, and potassium were statistically different for Arizona soils and vanadium, nickel, iron and aluminum concentrations were statistically different for New York soils. Zinc was the only element with high R2 and low p-value.
Pollution load index (PLI), enrichment factors (EF), and geo-accumulation index (Igeo) were calculated for both methods using U.S. Geological Survey data. The PLI were greater than 1, indicating soil pollution in the two states. Between pXRF and ICP-MS, the Igeo and EF in Arizona had similar degree of contamination for most elements except zinc in garden and lead in yard, respectively. For New York, the Igeo of arsenic, copper, and zinc differed by only one classification index between the two methods. The pXRF was reliable in determining arsenic, barium, calcium, copper, manganese, lead, and zinc in impacted communities.
This study shows that pXRF can be a cost-effective alternative to using ICP-MS techniques to screen soil samples for several environmentally relevant contaminants to protect environmental public health.
Publication:
Alqattan ZA, Artiola JF, Walls D, Ramírez-Andreotta, MD. Evaluating the portable X-ray fluorescence reliability for metal(loid)s detection and soil contamination status. Environ Monit Assess 196, 765 (2024). https://doi.org/10.1007/s10661-024-12893-8