We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Remediating Naturally Occurring Radioactive Materials and Other Contaminants in Groundwater Using Locally Prepared Activated Charcoal
Summary
Researchers in Ghana found that some groundwater used for drinking contained radioactive radon gas and other contaminants at levels exceeding safety guidelines. They discovered that a simple, low-cost water filter made from activated charcoal derived from coconut husks removed up to 98% of the radon and significantly reduced other harmful substances, offering an affordable solution for rural communities that lack access to expensive water treatment systems.
Introduction Most rural and peri-urban inhabitants in Ghana obtain their drinking water primarily from groundwater. However, groundwater quality is threatened by the presence of pollutants, including toxic metals, naturally occurring radioactive materials, hydrocarbons, trace organic contaminants, pesticides, nanoparticles, microplastics, and other emerging contaminants, posing risks to human health, ecological systems, and sustainable socioeconomic development. Methods This study evaluated groundwater quality using chemical and radiological analyses. In addition, a locally produced material (activated charcoal) was developed and tested for the removal of chemical and radiological contaminants from groundwater. Results Groundwater in Teiman, Ghana, showed Rn-222 concentrations ranging from 1 to 35 Bq L −1 (mean: 8.4 ± 6.1 Bq L −1 ), with 19% of samples exceeding the USEPA limit of 11 Bq L −1 . Activated charcoal reduced Rn-222 concentrations by 71–98% (mean: 89 ± 8%). The mean pre-treatment ingestion and inhalation doses were 21.5 µSv yr −1 and 17 µSv yr −1 , respectively, and were reduced after treatment. Other NORMs included Ra-226 (0.08–0.81 Bq L −1 ), Ra-228 (0.05–0.62 Bq L −1 ), and Th-232 (0.03–0.58 Bq L −1 ). Annual effective doses ranged from 0.06 to 0.26 µSv yr −1 (ingestion) and from 0.26 to 1.15 µSv yr −1 (inhalation), which were below the WHO guideline value of 0.1 mSv yr −1 but still warrant reduction. Locally prepared CaCl 2 -activated charcoal derived from coconut husk reduced Ra-226 and Ra-228 by 71 ± 9%, Th-232 by 58 ± 11%, EC and TDS by approximately 42%, and cation and anion concentrations by 54–92%. The pH increased from 6.2 ± 0.4 to 7.5 ± 0.3, which falls within the WHO recommended range of 6.5–8.5. Discussion The results showed varying percentage reductions in the physicochemical parameters and radionuclide activity concentrations studied. Activated charcoal prepared from coconut husk demonstrated significant potential for removing chemical and radiological contaminants from groundwater. Conclusion Activated charcoal prepared from coconut husk demonstrated significant potential for removing chemical and radiological contaminants from groundwater. The low-cost filter is scalable for use in rural communities.