Emission of volatile organic compounds (VOCs) from photocopiers was investigated to assess the potential health impacts on inhalation exposure to VOCs. VOCs samples were collected during working hours using SKC VOCs 575 series passive sample. Twenty-one quantified VOCs were measured and analyzed by GC-MS/MS. The results showed that the total VOCs concentration emitted in the photocopy centers A and B were 2.29×104 and 2.32×104 µg/m3, respectively. The highest detected chemical was trans-1,2-Dichloroethene at about 2.18×104 (photocopy center A) and 2.15×104 µg/m3 (photocopy center B (The results reveal that the non-carcinogenic risk for inhalation exposure to m-Xylene, p-Xylene, and trans-1,2-Dichloroethene were in the range 0.94-1.53 and 1.19-1.79 and 51.54-52.23, respectively, resulting in the hazard index (HI) of non-carcinogenic VOCs in total being greater than 1.0. This indicated that the cumulative effects of inhalation exposure to VOCs at low concentrations should be of concern, even though it does not exceed the occupational exposure limits and Threshold Limit Values-Time Weighted Average for the mixtures (TLV-TWAmix). Plants display a greener solution to reduce indoor air pollution. The bio-concentration levels of total VOCs in Epipremnum aureum were noted as 74.71 to 174.42, signifying that E. aureum is effective for removal of VOCs naturally and sustainably.

Genotoxicity model is developed to assess the individual subacute toxicity of benzene, toluene, ethylbenzene, and xylene (BTEX) at very low levels as in a landfill gas. Golden Pothos (Epipremnum aureum), a higher plant, was tested under variation of benzene 54-5656 ng/L, toluene 10-4362 ng/L, ethylbenzene 28-4997 ng/L, xylene 53-4845 ng/L, for 96 h. DNA fragmentation in plant leaves were investigated via comet assay. The results show that DNA migration ratio increased with the BTEX concentrations, but at different rates. The 50% effective concentration (EC) of DNA fragmentation from the dose-response relationships indicated toluene has the highest EC value and followed by benzene, xylene and ethylbenzene. Alternatively, ethylbenzene has the highest toxicity unit and followed by xylene, benzene and toluene as described by toxicity unit (TU). In conclusion, comet assay of Pothos can be used in differentiating DNA fragmentation against very low levels of BTEX in the atmosphere. Pothos is recommended for genotoxicity assessment of a low BTEX contaminated atmosphere.

Environmental contaminations with pesticides are considered as one of the major environmental pathways of human exposure leading to a potential threat to human health, especially if there is an accumulation in the trophic levels. This study purposed to investigate the level of pesticide residues and the potential health risk associated with vegetables, surface water, and sediment obtained from the river basin area. The concentrations of 87 pesticides from four main groups namely; organophosphate, organochlorine, pyrethroid, and persistent organic pollutants (POPs) were verified by triple quadrupole GC-MS/MS. The concentration of Parathion methyl, Methidathion, Bromophos methyl, Chlorfenvinphos, Triazophos, Azinphos ethyl, and D-trans-Phenothrin in the sediment samples ranged from 12.99-19.95 μg kg-1. The surface water sample mainly contains p, p'-DDT <0.012 μg L-1 followed by Endrin and Dieldrin <0.08 μg L-1, and Aldrin, Alpha-BHC, Heptachlor <0.004 μg L-1, respectively. The PTI was detected at 0.4 in the sum of surface water samples. The detectable pesticide residues were found in 95% of 20 vegetable samples. The positive of screening vegetables were most obviously contaminated with organophosphate (95%) followed by pyrethroid (40%), organochlorine (20%) and POPs (5%), respectively. The highest concentration of 0.04 mg kg-1 was recorded for Dicrotophos in Kitchen mint (Mentha cordifolia Opiz ex Fresen). Fenpropathrin recorded the lowest concentration of 3.2x10-3 mg kg-1 in corn (Zea mays L.). The highest PTI (31.20) was found in corn. The combined risk index of pesticide residues showed significant health risk to humans more than individual risk index. The health risk indices show that the detected pesticides considered a serious public health problem in the studied area, and there is a need to increment their monitoring to reduce their misuse.

The issue of greenhouse gas (GHG) emissions from municipal solid waste (MSW) is important in the context of climate change. Reduction of GHGs from waste disposal systems is one of the management strategies forming part of Thailand’s National Economic and Social Development Plan. This project evaluated emissions from a municipal solid waste system covering transportation and disposal in Lampang Municipality, northern Thailand. GHG emissions from transportation were estimated by the Institute for Global Environmental Strategies (IGES) based on the travel distance of the vehicles, using a vehicle emission model and vehicle fuel consumption. GHG emissions during the disposal process were also estimated based mainly on the model of IGES. The results indicated that GHG emissions from sanitary landfill were highly dominated by methane (CH4) emissions (20,346 tons CO2eq a-1). In addition, carbon dioxide (CO2) was emitted (226 tons a-1) from the transportation process. This evaluation found that GHG emission estimates based on travel distance were lower than those based on fuel consumption (44 %). Furthermore, changing from diesel fuel to compressed natural gas will reduce transportation emissions by approximately 7 %.

No abstract