Occurrence, potential sources, and risk assessment of pharmaceuticals and personal care products in atmospheric particulate matter in Hanoi, Vietnam.

Pharmaceutical and personal care products (PCPPs) were recently recognized as emerging pollutants due to their potential for adverse health and environmental impacts. One potential route of exposure, atmospheric particulate matter (APM), for polar PPCP chemicals has to date received limited attention. This study screened for 190 polar PPCP chemicals in outdoor APM samples collected from two locations in Hanoi, Vietnam, and predictions of source and potential effects on human health are presented. Day and night, as well as dry and rainy seasonal samples, were taken, and samples screened by LC-TOF, using sequential window acquisition and all theoretical fragment ion spectra method. Eleven PPCP chemicals were detected above the LOD and in more than one sample. The ∑11PPCP chemicals ranged from 0.61 to 21.9 ng m-3 (median 2.07 ng m-3), with between 2 and 6 compounds identified in individual samples (median 4). The ∑11PPCP chemicals collected near a heavy traffic area was greater than that in a populated residential zone. Night concentrations were significantly greater than day in both dry and rainy seasons (p < 0.05). Butyl methoxydibenzoylmethane, benzophenone-3, acetaminophen, cotinine, and fluorescent brightener 71 were detected in > 50% of samples. These are typically found in sunscreens, cosmetics, antipyretics, tobacco, and dyes. The DIair, hazard quotient (HQ), and hazard index (HI) for adults and children at sampling sites were estimated. The HQ for both adults and children were orders of magnitude less than the risk or were close to or whichever. APM does appear to be a potential additional secondary exposure source of PPCP chemicals to the environment and more work is needed to identify if sources are local or ubiquitous and if there is a greater health risk.

Occurrence and risk assessment of herbicides and fungicides in atmospheric particulate matter in Hanoi, Vietnam.

Vietnam is a Southeast Asian developing country with rapidly increasing air pollution, especially in large cities. Over 350,000 chemicals and chemical mixtures are produced and used in Vietnam; however, the country has only implemented air quality standards for 44 substances, which are primarily focused on inorganic and volatile organic compounds. Although numerous pesticides are frequently applied across large cities in Vietnam, information on their concentrations in atmospheric particulate matter (APM) is limited. Therefore, to investigate their occurrence and health effects, 187 pesticides in APM were screened using the liquid chromatography-mass spectrometry-quadrupole time of flight- Sequential Window Acquisition of All Theoretical Fragment Ion Spectra method (LC-QTOF-MS-SWATH). A total of 22 pesticides (16 fungicides and 6 herbicides) were quantified in the dry and rainy seasons. Among them, 19 substances were quantified in APM for the first time in Vietnam. Their median total concentrations in the dry season were higher than those in the rainy season, and the concentrations in the daytime were one-third of the night-time concentrations in both seasons. Their total levels ranged from 0.82 to 21.1 ng m-3 (median, 3.63 ng m-3), the detection frequencies of 9 pesticides were higher than 70%, and 7-14 pesticides were detected per sample (median, 10). Some of the detected pesticides were likely sourced from their prevalent use in amenity turf protection (e.g., in parks and public roads) and weed control (e.g., in gardens, floriculture, and agriculture). The total daily intake (DIair) values for adults, children, and infants were 8.17E-06, 2.06E-05, and 2.45E-05 mg kg-1 d-1, respectively, and the highest Hazard Quotients (HQs) were 4.81E-04, 1.22E-03, and 1.44E-03, respectively. All HQs and HIs of the pesticides were < 1 for all population groups (adults, children, and infants), indicating negligible exposure risks.

Comprehensive study of insecticides in atmospheric particulate matter in Hanoi, Vietnam: Occurrences and human risk assessment.

Air pollution is the most serious environmental issue in Vietnam, particularly in big cities. Air pollutants that are set as environmental standards are regularly monitored by the public institutions. Whereas, environmental data on organic micro-pollutants in atmospheric particulate matters (APMs) is limited, including PAHs and POPs. Although massive pesticides are used in big cities, their data in APMs in Vietnam is very scarce. In order to elucidate their occurrence in the ambient air in Hanoi and their health effects, we surveyed 107 insecticides in APMs by a novel target screening method using LC-QTOF-MS-SWATH. A total of 19 insecticides were detected in the dry and the rainy seasons. Among them, 16 substances are, to our knowledge, reported for the first time in the literature. Their total concentrations varied from 0.47 to 27.0 ng m-3 (median, 3.6 ng m-3), detection frequencies of 12 compounds are higher than 42%, and the number of insecticides detected per each sample ranging from 5 to 13 (median, 9). Total concentrations in the dry season were generally higher than in the rainy season, and concentrations at night were higher than daytime in both seasons. The level of insecticides depends not only on the season, but also on its physicochemical properties, its application conditions, and the meteorological conditions. Their emission sources could be related to agricultural usage, floricultural activities, and pest control in houses. The total maximum daily intake (DIair) through inhalation for adults and children were 2.39E-05 mg kg-1 d-1 and 2.98E-05 mg kg-1 d-1, respectively. The highest Hazard Quotients (HQs) were 1.34E-03 and 3.37E-03, and the highest Hazard Indices (HIs) were 2.71E-03 and 6.33E-03 for adults and children, respectively. All values of HQs, and HIs of insecticides were less than 1, indicating that health risk would be negligible.

Behavior of butachlor and pyrazosulfuron-ethyl in paddy water using micro paddy lysimeters under different temperature conditions in spring and summer.

The behavior of butachlor and pyrazosulfuron-ethyl in paddy water was investigated using micro paddy lysimeters with prescribed hydrological conditions under ambient temperature in spring and summer for simulating two rice crop seasons. Although they were not significantly different, the dissipation of both herbicides in paddy water in the summer experiment was faster than in the spring experiment. The half-lives (DT(50)) in paddy water for spring and summer experiments were 3.2 and 2.5 days for butachlor, and 3.1 and 1.6 days for pyrazosulfuron-ethyl, respectively.