Road Dust as a Significant Radiocesium Transporter from Land to River.

This study made it clear that road dust plays an important role for Cs-137 dynamics emitted by the Fukushima Daiichi nuclear power plant accident. It was proved from the Cs-137 and heavy metals determination in road dust, drainage gutter sediment beside pavement, and riverbed sediment around the inflow point of the gutter. Road dust and drainage gutter sediment contained significantly higher concentrations of Cs-137 and Cr, Ni, Cu, Zn, Mo, Cd, Sn, Sb, and Pb than riverbed sediment. These heavy metals are typically enriched in road dust in general and originate in anthropogenic sources. Concentrations of Cs-137 and the heavy metals were higher in riverbed sediments at the inflow point of drainage than in non-inflow points. Drainage gutter sediments exhibited Cs-137 and heavy metal accumulation at the downmost of the gutter, which is the inflow point into the river. Accordingly, distribution of Cs-137 and the heavy metals concentrations were consistent with each other. Moreover, the concentrations of Cs-137 and heavy metals were correlated positively and significantly, with different proportions between sampling sites but similar between sample type and survey date. This indicates that the discharge of Cs-137 and heavy metals is characteristic of the features of the locations, such as Cs-137 and heavy metals concentrations, (micro-) topography, structure of the road and gutter, pavement area, traffic density, and so on. We conclude that road dust is a major medium of Cs-137 transport from land into aquatic ecosystems.

Enrichment and Bioavailability of Trace Elements in Soil in Vicinity of Railways in Japan.

This study focuses on the concentrations, distribution, pollution levels, and bioavailability of 12 trace elements in soils along 6 different railways in Japan. Three diesel powered railways and three electricity powered railways were chosen as target. Surface soils (< 3 cm) were collected in vicinity of railways for analysis. Digestion and extraction were performed before concentration and bioavailability analysis. Enrichment factor was applied to investigate contamination levels of selected elements. The mean concentrations of Cr, Co, Ni, Cu, Zn, Sn, and Pb in soil samples were higher than soil background value in Japan. Concentrations of trace elements in soils along different railway had different characteristics. Horizontal distribution of Cu, Zn, Cd, Sn, and Pb in soil samples showed obviously downtrend with distance along railways with high frequency. Concentrations of V, Mn, Fe, and Co were higher in soils along railways which pass through city center. According to principal component analysis and cluster analysis, concentrations of Cu, Zn, Sn, and Pb could be considered as the indicators of soil contamination level along electricity powered trains, whereas indicators along diesel powered trains were not clear. Enrichment factor analysis proved that operation of freight trains had impact on pollution level of Cr, Ni, and Cd. Bioavailability of Mn, Co, Zn, and Cd in soil along electricity-powered railways were higher, and bioavailability of Pb in railways located in countryside was lower. Thus, enrichment and bioavailability of trace elements can be indicators of railway-originated trace elements pollution in soil.

Seasonal movement of trace-element discharge in a typical south-Indian suburban community.

Four conventional activated sludge sewage treatment plants (STPs) in Southern India were chosen to investigate the occurrence of major ions and trace metals in dissolved fraction of the wastewater. Samples were collected from inlet and outlet of STPs during the pre-monsoon and monsoon seasons. Except for a few elements (Mn, Mo and Ni), the concentrations of the rest increased at the outlet of STPs, suggesting that there is an addition of these elements during the treatment process. The increase in concentrations at the STP outlet ranged from 1.25 times for Mn to 3,254 times for Ag during the pre-monsoon. In the monsoon, the increase ranged from 1.75 (Fe) to 1,510 (Ag). This suggests that there is a substantial anthropogenic input of these elements as they pass through the treatment process. Removal rates of elements in STPs also varied. 59% of Mn was removed during the treatment process during pre-monsoon as compared to 67% removal during monsoon.

Determination of the Extent of Trace Metals Pollution in Soils, Sediments and Human Hair at e-Waste Recycling Site in Ghana.

The concentrations of trace elements (Mg, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Y, Mo, Cd, In, Sn, Sb, Cs, Ba, Tl, Pb, and Bi) in soils, sediment, human hair, and foodstuff collected around the electronic waste (e-waste) recycling sites in Accra, Ghana were detected using inductively coupled plasma-mass spectrometry (ICP-MS). High levels of Cu, Zn, Mo, Cd, In, Sn, Sb, and Pb were observed in soils collected from the e-waste recycling sites. Four sequential extraction procedures were used to evaluate the mobility and bioavailability of metals (Cu, Zn, Cd, Sb, and Pb). Especially, the results showed that Cd and Zn in soils were mostly recovered in exchangeable fraction (respectively 58.9 and 62.8%). Sediment collected from around the site had enrichment of Zn, Sn, Sb, Mo, In, Pb, and Bi. The concentrations of Cu, Mo, Cd, Sb, and Pb in human hair were significantly higher than those collected from the control site (p < 0.01). Additionally, hierarchical cluster analysis reviewed that these elements were derived from e-waste activities. The results of Pb isotopic ratios in the samples indicate that Pb in human hair possibly originated from contaminated soils, fish, and foodstuff.

Has irrigated water from Mahaweli River contributed to the kidney disease of uncertain etiology in the dry zone of Sri Lanka?

The Mahaweli is the largest river basin in Sri Lanka that provides water to the dry zone region through multipurpose irrigation schemes . Selenium, arsenic, cadmium, and other bioimportant trace elements in surface waters of the upper Mahaweli River were measured using ICP-MS. Trace element levels were then compared with water from two other rivers (Maha Oya, Kalu Ganga) and from six dry zone irrigation reservoirs. Results showed that the trace metal concentrations in the Mahaweli upper catchment were detected in the order of Fe > Cu > Zn > Se > Cr > Mn > As > Ni > Co > Mo. Remarkably high levels of Ca, Cr, Co, Ni, Cu, As, and Se were observed in the Mahaweli Basin compared to other study rivers. Considerably high levels of Cr, Mn, Fe, Co, Ni, Cu, Zn, As, and Se were found in upstream tributaries of the Mahaweli River. Such metals possibly originated from phosphate and organic fertilizers that are heavily applied for tea and vegetable cultivations within the drainage basin. Cadmium that is often attributed to the etiology of unknown chronic kidney diseases in certain parts of the dry zone is much lower than previously reported levels. Decrease in these metals in the lower part of the Mahaweli River could be due to adsorption of trace metals onto sediment and consequent deposition in reservoirs.

Stable cesium uptake and accumulation capacities of five plant species as influenced by bacterial inoculation and cesium distribution in the soil.

The effects of inoculation with Bacillus and Azospirillum strains on growth and cesium accumulation of five plant species, Komatsuna, Amaranth, sorghum, common millet and buckwheat, grown on cesium-spiked soil were assessed for potential use in cesium remediation. Pot experiments were performed using "artificially" Cs-contaminated soil. Three treatments were applied based on Cs location in the soil. For a soil height of 15 cm in the pots, Cs was added as follows: in the top five cm to imitate no ploughing condition; in the bottom five cm simulating inverted ploughing; and uniformly distributed Cs reproducing normal plowing. Generally, inoculation of Cs-exposed plants significantly enhanced growth and tolerance to this element. Transfer factor (ratio of Cs concentration in the plant tissues to that in surrounding soil) was strongly influenced by Cs distribution, with higher values in the top-Cs treatment. Within this treatment, inoculation of Komatsuna with Bacillus and Azospirillum strains resulted in the greatest transfer factors of 6.55 and 6.68, respectively. Cesium content in the shoots was high in the Azospirillum-inoculated Komatsuna, Amaranth, and buckwheat, i.e., 1,830, 1,220, and 1,030 µg per pot, respectively (five plants were grown in each pot). Therefore, inoculation of Komatsuna and Amaranth with the strains tested here could be effective in enhancing Cs accumulation. The decrease of Cs transfer under uniform- and bottom-Cs treatments would suggest that countermeasures aiming at decreasing the transfer of Cs could rely on ploughing practices.

Establishment of a primary hepatocyte culture from the small Indian mongoose (Herpestes auropunctatus) and distribution of mercury in liver tissue.

The present study established a primary hepatocyte culture for the small Indian mongoose (Herpestes auropunctatus). To determine the suitable medium for growing the primary hepatic cells of this species, we compared the condition of cells cultured in three media that are frequently used for mammalian cell culture: Dulbecco's Modified Eagle's Medium, RPMI-1640, and William's E. Of these, William's E medium was best suited for culturing the hepatic cells of this species. Using periodic acid-Schiff staining and ultrastructural observations, we demonstrated the cells collected from mongoose livers were hepatocytes. To evaluate the distribution of mercury (Hg) in the liver tissue, we carried out autometallography staining. Most of the Hg compounds were found in the central region of hepatic lobules. Smooth endoplasmic reticulum, which plays a role inxenobiotic metabolism, lipid/cholesterol metabolism, and the digestion and detoxification of lipophilic substances is grown in this area. This suggested that Hg colocalized with smooth endoplasmic reticulum. The results of the present study could be useful to identify the detoxification systems of wildlife with high Hg content in the body, and to evaluate the susceptibility of wildlife to Hg toxicity.

Bioaccumulation and metabolism of polybrominated diphenyl ethers (PBDEs) in coenobitid hermit crabs from marine litter-polluted beaches in remote islands.

Plastic litter containing additives is potentially a major source of chemical contamination in remote areas. We investigated polybrominated diphenyl ethers (PBDEs) and microplastics in crustaceans and sand from beaches with high and low litter volumes on remote islands that were relatively free of other anthropogenic contaminants. Significant numbers of microplastics in the digestive tracts, and sporadically higher concentrations of rare congeners of PBDEs in the hepatopancreases were observed in coenobitid hermit crabs from the polluted beaches than in those from the control beaches. PBDEs and microplastics were detected in high amounts in one contaminated beach sand sample, but not in other beaches. Using BDE209 exposure experiments, similar debrominated products of BDE209 in field samples were detected in the hermit crabs. The results showed that when hermit crabs ingest microplastics containing BDE209, BDE209 leaches out and migrates to other tissues where it is metabolized.

Monthly Dynamics of Plasma Elements, Hematology, Oxidative Stress Markers, and Hormonal Concentrations in Growing Male Shiba Goats (Capra hircus) Reared in Tokyo-Japan.

From a clinical point of view, the establishment of laboratory variables during the first few months of an animal's life helps clinicians to make sure they base their medical decisions on laboratory values for the specific breed and age group. The present study aimed to investigate the monthly dynamics in some plasma elements, hematology, reproductive hormones, and oxidative stress marker profiles during the first five months of age (neonatal and peri-puberty stage) in male Shiba goat's kids. Sixteen kids were investigated from the first to the fifth month (M1 to M5), and the data were presented as the statistical difference between them. Whole blood and plasma samples were collected monthly for analysis of basal hematology, plasma elements concentration (trace elements: Cu, Zn, Se, Fe, and Cr; macroelements: Ca and Mg), circulating hormones (cortisol, FSH, LH, IGF1, immunoreactive inhibin, testosterone, T3, and T4), and oxidative stress markers (MDA, CAT, SOD, and GPX). The results showed age-related changes in the observed parameters. The fifth month recorded the lowest level of almost all investigated minerals, except for Cr. Plasma hormone levels revealed age-dependent increases in IGF-1 and testosterone, age-related decreases in T3 and T4, and non-significant changes in cortisol and FSH. Besides, the concentrations of inhibin and LH were significantly higher at M1-M3 compared with M4-M5. Plasma SOD, GPX, and CAT were increased with age. In conclusion, age-related changes and a distinction of age in months was found necessary to interpret the laboratory results, specifically in terms of age in months and the peri-puberty stage in young goats, which are important to follow up the age-specific diseases, reproductive status, and treatment follow-ups in this stage.

Association between working overtime and psychological stress reactions in elementary and junior high school teachers in Japan: a large-scale cross-sectional study.

This study aimed to investigate the relationship between working overtime and psychological stress reactions among school teachers. It also evaluated the interaction of overtime work types (on weekdays, on holidays, and bringing work home) and task content (educational, peripheral and both). This cross-sectional study was conducted on Japanese elementary and junior high school teachers. Primary outcome was psychological stress reactions measured with the Brief Job Stress Questionnaire. Participants were asked how long they work overtime on weekdays, holidays, and at home. Participants were also asked whether they engaged in educational tasks and/or peripheral tasks during that overtime work. Multiple linear regression analyses were applied and 6,135 participants were included in the analyses after imputing missing data. Working hours of all three types were significantly correlated with higher psychological stress reactions. Moreover, engaging in both educational and peripheral tasks showed higher psychological stress reactions than in only educational tasks when working overtime on weekdays and holidays. In conclusion, reducing overtime work regardless of work types is crucial for mitigating psychological stress reactions for teachers. It might also be possible to manage the psychological stress reactions by splitting the role of task contents, when working overtime on weekdays and holidays at school.

Association of Routine Chlamydia trachomatis Screening During Pregnancy and Seroprevalence of Chlamydial Infection in Children, 1991-2015.

We performed a seroepidemiologic study of sera from children in Brooklyn, New York, before and after the implementation of prenatal chlamydial screening almost 20% of children aged ≤10 years in the prescreening group had anti-Chlamydia trachomatis immunoglobulin G compared with none in the postscreening group.

The utility of electrocardiography and echocardiography in copper deficiency-induced cardiac damage in goats.

Copper deficiency (CuD) is a common mineral disorder in ruminants, which causes histomorphological changes in the heart due to disturbances in copper-dependent metalloenzymes. However, alterations in the measurable cardiac parameters during CuD have not been studied in ruminants, especially in goats. Therefore, the current study aimed to investigate longitudinally the potential role of electrocardiography (ECG) and echocardiography to detect the CuD-induced cardiac damage at different time intervals and concomitantly highlighting the impact of CuD on specific hemato-biochemical parameters and histological cardiac disruption in goats. Eight Shiba goats were included and divided into two equal groups; copper adequate (CuA) as a control and copper-deficient (CuD) that supplemented with copper-chelating agents (sulfur 3 g/kg DM and molybdenum 40 mg/kg DM). The hemato-biochemical analysis, ECG assessment at the base apex lead, and right-side echocardiography were performed just before the experimental onset (T0), and later on at two-time intervals after existing of CuD, at the fifth (T5) and seventh (T7) months. Necropsy and histopathological examination of the heart were performed at the end of the experiment. In the CuD group, the heart dimensions at T5 and T7 showed significant increase in QRS duration, ST-segment duration, the left atrial area in systole, left ventricular diameter and volume in diastole, stroke volume, and cardiac output compared with CuA (P < 0.05). Also, myocardial degeneration, necrosis, and fibrosis were evidenced with a concurrent increase of plasma creatine kinase, lactate dehydrogenase, aspartate aminotransferase, and cardiac troponin I (P < 0.05). In conclusion, CuD disturbs hemato-biochemical parameters and results in myocardial damage and cardiac dilatation that increases some ECG and echocardiographic parameters without development of systolic dysfunction. The ECG and echocardiography can potentially detect cardiac changes in long-lasting CuD in goats.

Contributions of apoplasmic cadmium accumulation, antioxidative enzymes and induction of phytochelatins in cadmium tolerance of the cadmium-accumulating cultivar of black oat (Avena strigosa Schreb.).

The contributions of cadmium (Cd) accumulation in cell walls, antioxidative enzymes and induction of phytochelatins (PCs) to Cd tolerance were investigated in two distinctive genotypes of black oat (Avena strigosa Schreb.). One cultivar of black oat 'New oat' accumulated Cd in the leaves at the highest concentration compared to another black oat cultivar 'Soil saver' and other major graminaceous crops. The shoot:root Cd ratio also demonstrated that 'New oat' was the high Cd-accumulating cultivar, whereas 'Soil saver' was the low Cd-accumulating cultivar. Varied levels of Cd exposure demonstrated the strong Cd tolerance of 'New oat'. By contrast, low Cd-accumulating cultivar 'Soil saver' suffered Cd toxicity such as growth defects and increased lipid peroxidation, even though it accumulated less Cd in shoots than 'New oat'. Higher activities of ascorbate peroxidase (EC 1.11.1.11) and superoxide dismutase (EC 1. 15. 1. 1) were observed in the leaves of 'New oat' than in 'Soil saver'. No advantage of 'New oat' in PCs induction was observed in comparison to Cd-sensitive cultivar 'Soil saver', although Cd exposure increased the concentration of total PCs in both cultivars. Higher and increased Cd accumulation in cell wall fraction was observed in shoots of 'New oat'. On the other hand, in 'Soil saver', apoplasmic Cd accumulation showed saturation under higher Cd exposure. Overall, the present results suggest that cell wall Cd accumulation and antioxidative activities function in the tolerance against Cd stress possibly in combination with vacuolar Cd compartmentation.

Changes in copper, zinc and cadmium distributions in the liver of Formosan squirrels with characteristic high copper accumulation.

We discovered previously that Formosan squirrels (Callosciurus erythraeus) accumulate copper (Cu) in their livers at levels averaging 1700 µg per dry g (approximately 420 µg per wet g). In the current study, we investigated the relationship between Cu accumulation and hepatic injury, and we determined the distribution and chemical form of Cu in the liver supernatant. In particular, we explored the role of metallothionein in the liver supernatant. We observed no significant differences in hepatic Cu concentration between squirrels that showed pathological changes in the liver and those that did not. Serum alanine aminotransferase activity did not increase with increasing hepatic Cu concentration. These results suggest that abnormal Cu accumulation in the livers of Formosan squirrels does not induce severe hepatic injury. We found that 26.7% of the Cu in the liver was distributed to the supernatant, and only 11.0% of the Cu in the liver was bound to metallothionein, suggesting that metallothionein in the hepatic supernatant does not contribute to detoxification of excess Cu in Formosan squirrels.

Immutable heavy metal pollution before and after change in industrial waste treatment procedure.

This study compared state of pollution around an intermediate treatment plant of industrial wastes before and after the change of its treatment procedure. Bulk atmospheric deposition, surface soil, suspended particulate matter and groundwater were collected after the plant changed main operation to waste crushing and volume reduction. Their heavy metals content were comparatively investigated with the previous results obtained when it was burning wastes. The bulk heavy metals deposition showed a clear distance-related attenuation both in burning and crushing periods, indicating that the plant was the main emissions source in either case. High concentrations of heavy metals in suspended particles, soil, and groundwater during the crushing period indicated their diffusion to water environment over time. The bulk atmospheric heavy metals deposition decreased significantly, 0.20~ 0.49 times for Cu, Zn, Cd and Pb and 0.69~0.94 times for Cr, during the crushing period than burning period. However, change of their enrichment factors was not significant. It may indicate that the pollution state did not change qualitatively in a bulk deposition basis and quantitatively in a depositing particle basis. The results showed that heavy metals deposition is dominated by suspended and precipitated particulate matters that adsorb and transport the metals.

The impact of adenotonsillectomy on pediatric asthma.

OBJECTIVE: To determine asthma outcomes in children undergoing adenotonsillectomy (T&A) for treatment of sleep-disordered breathing (SDB). HYPOTHESIS: Asthmatic children will demonstrate improvement in asthma control after T&A compared to asthmatic children not undergoing surgical treatment. STUDY DESIGN: Prospective cohort. PATIENT-SUBJECT SELECTION: 80 children with diagnosed asthma, aged 4-11, undergoing T&A and 62 controls matched to the T&A subjects by age, sex, and asthma severity classification. METHODOLOGY: Parents and children completed the Childhood Asthma Control Test (C-ACT) and the Pediatric Sleep Questionnaire (PSQ). Parents were queried regarding the number of asthma exacerbations, the frequency of the use of systemic steroids, the number of emergency room visits and the number of hospitalizations in the prior 6 months. The identical questionnaires and interviews were completed 6 months after entry. RESULTS: The adjusted mean (95% CI) C-ACT score was 21.86 (20.94-22.68) at entry and 25.15 (24.55-25.71) at follow-up for the T&A group compared with 22.42 (21.46-23.28) and 23.59 (22.77-24.33) for the control group. There was a significant group by time interaction (P < 0.001). Simple effects analysis showed that group means did not differ at entry (P = 1.00) but did differ at follow-up (P = 0.006). Baseline PSQ was a significant predictor of improvement in C-ACT scores. Statistical modeling did not demonstrate significant group by time interactions for any of the asthma clinical outcomes, although these outcomes were very infrequent in both groups. CONCLUSION: Treatment of SDB improves asthma outcomes as measured by the C-ACT.

PA subunit of RNA polymerase as a promising target for anti-influenza virus agents.

RNA polymerase of influenza virus is a specific enzyme necessary for the viral replication. A siRNA against the RNA polymerase and the RNA polymerase inhibitor L-742,001 reduced accumulation of viral RNAs in the infected cells. L-742,001 strongly inhibited virus re-growth after removal of the agent from the culture, whereas the neuraminidase inhibitor zanamivir did not. L-742,001-resistant mutants showed a Thr-20 to Ala substitution in the PA subunit of RNA polymerase. The drug-resistant virus showed a slight reduction in the susceptibility to L-742,001 in both the plaque assay (threefold reduction) and enzyme assay (two- to three-fold reduction). The resistance levels were lower than those of zanamivir-resistant mutants in the plaque assay. Against zanamivir-resistant mutants, L-742,001 retained the same antiviral activity as against the wild-type strain. These results indicate that L-742,001 is most likely to act at the PA subunit, and possesses a unique profile. It is suggested that PA subunit of RNA polymerase is a promising target for anti-influenza virus agents.

Subcellular distribution and potential detoxification mechanisms of mercury in the liver of the Javan mongoose (Herpestes javanicus) in Amamioshima Island, Japan.

In a previous study, we showed that Hg accumulated to high levels in the liver of the Javan mongoose (Herpestes javanicus), a terrestrial mammal that lives on Amamioshima Island, Japan. This suggests a sophisticated mechanism of hepatic Hg detoxication. Assay of the subcellular localization of Hg and the expression of protective enzymes provides important clues for elucidating the mechanism of Hg detoxication. In the present study, the concentrations of 11 elements (Mg, Cr, Mn, Fe, Cu, Zn, Se, Rb, Cd, total Hg [T-Hg] and organic Hg [O-Hg], and Pb) were determined in the liver and in five liver subcellular fractions (plasma membrane, mitochondria, nuclei, microsome, and cytosol) of this species. As the T-Hg level increased, T-Hg markedly distributed to the plasma membrane. The T-Hg levels in all subcellular fractions correlated with Se levels. Although the T-Hg level in the microsomal fraction was relatively low, the ratio of O-Hg to T-Hg was significantly lower in the microsomes than in the other fractions. Significant positive correlations were found between the level of glutathione-S-transferase-pi, a marker of oxidative stress, and the O-Hg and T-Hg levels, but the correlation was better with O-Hg than with T-Hg. Western blot analysis of thioredoxin reductase 2 (TrxR2), a protein involved in protecting cells from mitochondrial oxidative stress, showed that the level of TrxR2 correlated with that of T-Hg. High TrxR2 levels may be one mechanism by which the Javan mongoose attenuates the toxicity of the high Hg levels present in the liver.

Trace element accumulations in 13 avian species collected from the Kanto area, Japan.

In the present study, concentrations of 13 elements (Li, Cr, Mn, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, Hg) were measured in the tissues of the livers, the kidneys, pectoral muscles, lungs and brains of 13 avian species collected from the Kanto area of Japan. The difference in hepatic heavy metal levels of the grey herons from the two sites was compared. Metal levels in the sediment of the Tama River estuary, situated in the Haneda area, were also measured. These results revealed that heavy metal pollution is present in an aquatic area of Haneda. The accumulation patterns of Cu and Zn in the livers of grey herons appeared to be separated into two groups. Additionally, the present study includes the properties of other metal accumulations and their relationships in avian species.

Accumulation of trace elements used in semiconductor industry in Formosan squirrel, as a bio-indicator of their exposure, living in Taiwan.

Concentrations of 17 trace elements were analyzed using inductively coupled plasma-mass spectrometry (ICP-MS) in Formosan squirrels (Callosciurus erythraeus) of Taiwan and Japan to document trace element pollution in Taiwan. High concentrations of elements used to produce semiconductors - Ga, As, Cd, In and Tl - were found in animals captured in Miaoli County, which is the nearest site to Hsinchu City, a chief city of Taiwan's semiconductor industry. Significant correlations between Ga, As, In and Tl were found in the kidney, liver, lung and muscle tissues of Taiwanese squirrels. Hierarchical cluster analysis indicated that Ga, As, In and Tl were of the same clade, indicating that Ga, As, In and Tl were discharged from an identical origin. Molar ratios of Ga/As concentration in lungs of animals captured in Miaoli resembled those of animals after intratracheal administration of particulate gallium arsenide (GaAs). This result might indicate that the higher concentrations of Ga and As in the specimens in Miaoli resulted from atmospheric exposure to GaAs.