Fluoride Action Network

Hydrogen fluoride concentrations in ambient air of an urban area based on the emissions of a major phosphogypsum deposit (SW, Europe)

Source: Science of The Total Environment Volume 714, 20 April 2020, 136891 | February 9th, 2020 | Authors: Torres-Sánchez R, Sánchez-Rodas D, Sánchez de la Campa AM, de la Rosa JD.
Location: Spain
Industry type: Phosphate Industry


  • Several HF impacts have been recorded and associated to the PG deposit.
  • Impacts are more numerous in winter but more concentrated in the warm season.
  • PG deposit is susceptible to emit HF through its solid and liquid phases.
  • The emission factors of the brines, settled in 2.7 kg/ha day, is the most important.


Hydrogen fluoride (HF) is one of the most toxic gaseous compounds in air, the primary anthropogenic source of which is industrial activity, specifically fertilizer and waste. HF concentrations in an urban area (Huelva, SW Spain) related to a nearby major phosphogypsum (PG) deposit were measured by passive sampling during summer and winter months from 2014 to 2017 and high-resolution sampling during 2017 and 2017–2018 using an HF analyser. An HF geochemical anomaly was found in the PG pond with average concentrations of up to 19.1 ug/m3, and concentrations of up to 1.6 ug/m3 were exhibited in the nearest urban area. The concentrations were associated with the HF emissions from the PG deposit. Emission factors were calculated by field and laboratory experiments, and the brines exhibited the highest emission factor (2.7 kg/ha day). Several impacts of HF (>0.1 ug/m3) in the city were recorded throughout the year, occurring at noon in the summer and during fog events in the winter. Consequently, the PG system should be restored to protect the population living in Huelva from the impacts of HF emission.