Improved isolation of cadmium from paddy soil by novel technology based on pore water drainage with graphite-contained electro-kinetic geosynthetics

Novel soil remediation equipment based on electro-kinetic geosynthetics (EKG) was developed for in situ isolation of metals from paddy soil. Two mutually independent field plot experiments A and B (with and without electric current applied) were conducted. After saturation using ferric chloride (FeCl3) and calcium chloride (CaCl2), soil water drainage capacity, soil cadmium (Cd) removal performance, energy consumption as well as soil residual of iron (Fe) and chloride (Cl) were assessed. Cadmium dissolved in the soil matrix and resulted in a 100% increase of diethylenetriamine-pentaacetic acid (DTPA) extracted phyto-available Cd. The total soil Cd content reductions were 15.20% and 26.58% for groups A and B, respectively, and electric field applications resulted in a 74.87% increase of soil total Cd removal. The electric energy consumption was only 2.17 kWh/m3 for group B. Drainage by gravity contributed to > 90% of the overall soil dewatering capacity. Compared to conventional electro-kinetic technology, excellent and fast soil water drainage resulted in negligible hydrogen ion (H+) and hydroxide ion (OH−) accumulation at nearby electrode zones, which addressed the challenge of anode corrosion and cathode precipitation of soil metals. External addition of FeCl3 and CaCl2 caused soil Fe and Cl residuals and led to 4.33–7.59% and 139–172% acceptable augments in soil total Fe and Cl content, correspondingly, if compared to original untreated soils. Therefore, the novel soil remediation equipment developed based on EKG can be regarded as a promising new in situ technology for thoroughly isolating metals from large-scale paddy soil fields

Closing the Implementation Gap: Bringing Clean Air to the Region

This report identifies 25 clean air measures that can positively impact human health, crop yields, climate change and socio-economic development, as well as contribute to achieving the Sustainable Development Goals. Implementing these measures could help 1 billion people breathe cleaner air by 2030 and reduce global warming by a third of a degree Celsius by 2050

Elevated Indoor Volatile Organic Compound Exposure in the Niger Delta Region of Nigeria

The implications of environmental contamination on human health in the Niger Delta region of Nigeria remain a topic of growing international public health interest. To better understand ongoing air pollution and initiate remediation efforts, the United Nations Environmental Programme (UNEP) report recommended the monitoring of volatile organic compounds (VOCs) across different media (water, soil, and air) in Ogoniland, an at-risk population in the Niger Delta region of Nigeria. In this pilot study, we measured indoor VOC concentrations in the indoor air of 20 households in Ogale, an Ogoniland community whose groundwater system is contaminated with benzene at levels 900 times the World Health Organization guidelines and evaluated self-reported health conditions and predicted cancer risks and hazards from inhalation exposure to VOCs. We detected higher concentrations of benzene (mean = 25.7 μg/m3, SD = 23.2 μg/m3) and naphthalene (mean = 7.6 μg/m3, SD = 13.8 μg/m3) than has been reported in other regions. Although study participants reported health symptoms consistent with VOC exposure, we were underpowered to detect a significant association between select indoor VOCs and these self-reported health symptoms using univariate logistic regression models. These findings suggest that that the health symptoms reported by participants may be poor proxies for the underlying disease processes associated with adverse health outcomes due to VOC exposure in this community and that the burden of adverse health effects due to VOC exposure may stem from the contaminated groundwater system. We estimated a non-cancer hazard quotient of 3 from exposure to naphthalene and lifetime excess cancer risks from exposure to naphthalene, benzene, p-dichlorobenzene, carbon tetrachloride, and ethylbenzene of 3 × 10−4, 2 × 10−4, 6 × 10−5, 6 × 10−6, and 1 × 10−5, respectively. These results exceed common risk benchmarks in the United States, suggesting a need for further studies to characterize VOC exposures, sources, and associated health risks in the Niger Delta

Airborne 2,5-dimethylfuran as a marker to indicate exposure to indoor tobacco and biomass burning smoke

Smoke from domestic tobacco smoking and biomass burning is the most harmful indoor air pollutant. This study aimed to evaluate 2,5-dimethylfuran (DMF) as a marker to indicate exposure to environmental tobacco smoke (ETS) and biomass burning smoke (BBS) in households. The evaluation consisted of three indoor air monitoring campaigns in (1) 8 apartments with different smoking scenarios, (2) 76 apartments in a Metropolitan city, and (3) 26 homes in two rural areas. All the air samples were collected in a passive way using thermal desorption (TD) tubes and analyzed by TD-gas chromatography/mass spectrometry (GC/MS). The indoor smoking experiments showed that TD tubes could detect DMF even when the occupant smoked one cigarette every day. In urban homes, DMF detection had a substantial agreement with smoking status, indicated by a Kappa coefficient of 0.67. In rural homes, DMF was detected at high concentrations in homes with biomass burning. Along with DMF, the TD tubes could detect and quantify over 70 other volatile organic compounds (VOCs), allowing exposure and risk assessment for indoor smoke. In conclusion, monitoring DMF with TD tubes offers an easy, low-cost approach to measure domestic ETS and BBS exposures. This method has the potential to measure exposure to outdoor smoke from wildfire and agricultural burning