04 July 2016
ISEH 2016 & Geoinformatics 2016: Joint International Conference on Environment, Health, GIS and Agriculture
14 August 2016
Members can keep in touch with their colleagues through short news and events articles of interest to the SEGH community.
Science in the News
Latest on-line papers from the SEGH journal: Environmental Geochemistry and Health
- Characteristics of PM 2.5 , CO 2 and particle-number concentration in mass transit railway carriages in Hong Kong 2016-06-20
Fine particulate matter (PM2.5) levels, carbon dioxide (CO2) levels and particle-number concentrations (PNC) were monitored in train carriages on seven routes of the mass transit railway in Hong Kong between March and May 2014, using real-time monitoring instruments. The 8-h average PM2.5 levels in carriages on the seven routes ranged from 24.1 to 49.8Â Âµg/m3, higher than levels in Finland and similar to those in New York, and in most cases exceeding the standard set by the World Health Organisation (25Â Âµg/m3). The CO2 concentration ranged from 714 to 1801Â ppm on four of the routes, generally exceeding indoor air quality guidelines (1000Â ppm over 8Â h) and reaching levels as high as those in Beijing. PNC ranged from 1506 to 11,570 particles/cm3, lower than readings in Sydney and higher than readings in Taipei. Correlation analysis indicated that the number of passengers in a given carriage did not affect the PM2.5 concentration or PNC in the carriage. However, a significant positive correlation (pÂ <Â 0.001, R 2Â =Â 0.834) was observed between passenger numbers and CO2 levels, with each passenger contributing approximately 7.7â€“9.8Â ppm of CO2. The real-time measurements of PM2.5 and PNC varied considerably, rising when carriage doors opened on arrival at a station and when passengers inside the carriage were more active. This suggests that air pollutants outside the train and passenger movements may contribute to PM2.5 levels and PNC. Assessment of the risk associated with PM2.5 exposure revealed that children are most severely affected by PM2.5 pollution, followed in order by juveniles, adults and the elderly. In addition, females were found to be more vulnerable to PM2.5 pollution than males (pÂ <Â 0.001), and different subway lines were associated with different levels of risk.
- Excessive fluoride consumption increases haematological alteration in subjects with iron deficiency, thalassaemia, and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency 2016-06-18
Excessive fluoride consumption leads to accelerated red blood cell death and anaemia. Whether that increases the haematological alteration in subjects with haematological disorders (iron deficiency, thalassaemia, and G-6-PD deficiency) is still unclear. The fluoride in serum and urine and haematological parameters of students at Mae Tuen School (fluoride endemic area) were analysed and compared to those of students at Baan Yang Poa and Baan Mai Schools (control areas). Iron deficiency, thalassaemia, and G-6-PD deficiency were also diagnosed in these students. The students at Mae Tuen School had significantly (PÂ <Â 0.001) higher levels of mean fluoride in the serum and urine than those in control areas. In both control and fluoride endemic areas, students with haematological disorders had significantly lower levels of Hb, Hct, MCV, MCH, and MCHC than those without haematological disorders. Moreover, the lowest levels of Hb, MCH, and MCHC were observed in the students with haematological disorders who live in the fluoride endemic area. Thus, the excessive fluoride consumption increased haematological alteration in subjects with iron deficiency, thalassaemia, and G-6-PD deficiency and that may increase the risk of anaemia in these subjects.
- Health risk assessment of potentially harmful elements and dietary minerals from vegetables irrigated with untreated wastewater, Pakistan 2016-06-18
In the developing world, vegetables are commonly grown in suburban areas irrigated with untreated wastewater containing potentially harmful elements (PHEs). In Pakistan, there is no published work on the bioaccessibility aspect of PHEs and dietary minerals (DMs) in sewage-irrigated soil or the vegetables grown on such soils in Pakistan. Several industrial districts of Pakistan were selected for assessment of the risk associated with the ingestion of vegetables grown over sewage-irrigated soils. Both the total and bioaccessible fraction of PHEs (Cd, Co, Cr, Ni, and Pb) and DMs (Fe, Cu, Mn, Zn, Ca, Mg, and I) in soils and vegetable samples were measured. The concentrations of these PHEs and DMs in sewage-irrigated and control soils were below published upper threshold limits. However, compared to control soils, sewage irrigation over the years decreased soil pH (7.7 vs 8.1) and enhanced dissolved organic carbon (1.8 vs 0.8Â %), which could enhance the phyto-availability of PHEs and DMs to crops. Of the PHEs and DMs, the highest transfer factor (soil to plant) was noted for Cd and Ca, respectively. Concentrations of PHEs in most of the sewage-irrigated vegetables were below the published upper threshold limits, except for Cd in the fruiting portion of eggplant and bell pepper (0.06â€“0.08Â mg/kg Cd, dry weight) at three locations in Gujarat and Kasur districts. The bioaccessible fraction of PHEs can reduce the context of dietary intake measurements compared to total concentrations, but differences between both measurements were not significant for Cd. Since the soils of the sampled districts are not overly contaminated compared to control sites, vegetables grown over sewage-irrigated soils would provide an opportunity to harvest mineral-rich vegetables potentially providing consumers 62, 60, 12, 104, and 63Â % higher dietary intake of Cu, Mn, Zn, Ca, and Mg, respectively. Based on Fe and vanadium correlations in vegetables, it is inferred that a significant proportion of total dietary Fe intake could be contributed by soil particles adhered to the consumable portion of vegetables. Faecal sterol ratios were used to identify and distinguish the source of faecal contamination in soils from Gujranwala, Gujarat, and Lahore districts, confirming the presence of human-derived sewage biomarkers at different stages of environmental alteration. A strong correlation of some metals with soil organic matter concentration was observed, but none with sewage biomarkers.