Previous studies have demonstrated that organochlorine pesticide (OCP) exposure has a negative impact on the neurological function of infants. Only a few reports have investigated the thyroid and growth hormones and their relationship to neurodevelopment after human exposure to OCPs, especially in the case of infants. Our goal was to determine whether breastmilk OCP residues were associated with negative impacts and/or alterations in the neurodevelopment of infants among specific southern Taiwanese mother–breastfed infant pairs. Our subjects (n = 55 pairs) were recruited from southern Taiwan between 2007 and 2010. The thyroid and growth hormone levels in the cord blood samples collected after childbirth were determined. The breastmilk was gathered within one month after childbirth for the determination of OCP levels using a high-resolution gas chromatograph with mass spectrometry, and the neurodevelopment of 10–12-month-old infants was examined using the Bayley Scales of Infant and Toddler Development®, Third Edition (Bayley-III). It was observed that 4,4′-dichlorodiphenyl-dichloroethylene (4,4′-DDE) (mean = 10.3 ng/g lipid) was the most predominant OCP compound in the breastmilk samples. At higher concentrations (>75th percentile), specific OCPs were associated with significantly lower levels of thyroid and growth hormones than at lower concentrations (<75th percentile). Significantly higher odds ratios (ORs) were observed for binary cognitive (OR = 8.09, p = 0.025 for 4,4′-DDT), language (OR = 11.9, p = 0.013 for 4,4′-DDT) and social–emotional (OR = 6.06, p = 0.01 for trans-CHL) composite scores for specific OCPs belonging to the lower exposure group as compared to the higher OCP exposure group. The five domain Bayley-III infant neurodevelopment outcomes were negatively associated with specific OCPs in the breast milk samples based on the redundancy analysis (RDA) test. Bayley-III scales, which include cognitive, language, motor, social-emotional, and adaptive behavior scales, could be predicted by 4,4′-DDT, endrin, endosulfan I, heptachlor, or heptachlor epoxide using multivariate linear regression models with adjustment for maternal age, pre-pregnant BMI, parity, and infant gender. In conclusion, although our study showed that postnatal exposure to breast milk OCPs may be associated with infant neurodevelopmental outcomes and that prenatal exposure, if extrapolated from breastmilk levels, is associated with changes in thyroid and growth hormones that may have effects on neurodevelopment, these associations are only suggestive; thus, further studies are recommended for confirmation.

Because consumer products release them, polybrominated diphenyl ethers (PBDEs) are frequently present in a variety of indoor environments including homes and workplaces. Our goal was to investigate PBDEs contamination of workplace air-conditioner filter dust to assess the health effects of contaminated dust on workers with occupational exposure. Nine medical clinics, four dental clinics, eight factory offices, and six factory clean rooms were selected in southern Taiwan between April 2013 and September 2014. Air-conditioner-filter dust was collected by a high-efficiency vacuum cleaner and then PBDEs were analyzed by a high-resolution gas chromatography coupled with high-resolution mass spectrometry.

At the end of 2019, the coronavirus COVID-19 outbreak was first observed. Also known as Severe Acute Respiratory Syndrome Coronavirus 2 (SAS-cov-2), it rapidly spread globally in the first half of 2020. COVID-19 disease was well-controlled in Taiwan without a nation-wide lockdown. Our study aimed to investigate PM2.5 levels and patterns from PM2.5 sensors during the COVID-19 situation in 2020 compared with those in the corresponding periods in 2019. Our sampling areas were located at industrial areas in the north and south Taiwan and were used to gather PM2.5 data from approximately 1,500 PM2.5 sensors every 1 or 3 minutes between January and March of 2019 and 2020. Compared with the corresponding period of 2019 (16.3 and 32.4 μg m -3 in north and south Taiwan, respectively), PM2.5 was significantly reduced by 3.70% and 10.6% in north and south Taiwan, respectively, during the COVID-19 situation from January to March in 2020 based on a big data analysis. Similar PM2.5 patterns were observed in the industrial areas in north and south Taiwan in 2019 and 2020. Based on our results, the decline in PM2.5 during the COVID-19 outbreak has mainly been due to decreased domestic emissions of PM2.5 precursors (i.e., nitrogen dioxide and sulfur dioxide) and to a lesser degree is due to reductions in transboundary transportation of PM2.5, such as long-range PM2.5 transport from China. PM2.5 may be temporarily decreased during the COVID-19 outbreak, but the patterns remained similar to those in the past.Considering restrictions related to the rapid spread of the SAS-cov-2 virus during the COVID-19

Several studies have stated the harmful effects of PM 2.5 to population health, including disruption of neurological development. However, the mechanism behind the neurodevelopmental effects of ambient PM 2.5 and postnatal PBDEs and OCPs exposure is still unknown. Our goal was to determine influence of breastmilk residues, polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs), to the infants' neurodevelopment with respect to high and low PM 2.5 exposure areas. The participants were recruited from high PM 2.5 exposure areas (n = 32) and low PM 2.5 exposure areas (n = 23) of southern Taiwan. The extracted 14 PBDEs and 20 OCPs compounds were analyzed using gas chromatography coupled with mass spectrometer. The infants, aging from 8-12 months, were examined by Bayley Scales of Infants and Toddlers Development, Third Edition (Bayley-III) for neurodevelopment. Results showed that high PM 2.5 exposure caused reduced head circumference and had significant effects on the motor skill and social emotional development. For breastmilk PBDEs, a positive correlation between BDE-196 and social emotion, after multivariate analysis with adjustment of confounders, was observed while BDE-99, 196, 197, and 207 showed higher magnitudes in low PM 2.5 areas than in high PM 2.5 areas. For OCPs, only γ-hexachlorcyclohexanes (γ-HCH) presented the significant difference between high and low PM 2.5 exposure areas. Most breastmilk OCPs residues, including 4,4'-dichlorodiphenyltrichloroethane (4,4'-DDT), γ-HCH, endrin, and heptachlor epoxide showed negative impact on the Bayley-III scores after multivariate analysis. In conclusion, infants' neurodevelopment was significantly correlated with the location of PM 2.5 exposure and breastmilk intake of certain PBDEs and OCPs. Breastmilk OCPs might obviously affect infants' neurodevelopment more compared to breastmilk PBDEs based on our finding. Moreover, this study further employs awareness about viable effects of PM 2.5 in infants' neurodevelopment.