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This study explored how preservice teachers engaged in collaborative inquiry with elementary students to facilitate social justice and equity in science education. By inviting elementary students as key stakeholders into collaborative inquiry, we examined how preservice teachers uncovered critical problems of science education in underserved communities and how they (re)imagined science learning environments. We also investigated how collaborative inquiry with students shaped the preservice teachers' identities as science educators. Guided by the critical ethnography and data analysis spiral, we analyzed qualitative data related to 34 preservice teachers from a US teacher preparation program embedded in clinical residencies on elementary school sites. Our findings showed that preservice teachers: (1) leveraged collaborative inquiry to illuminate barriers and affordances to science learning; (2) became co-agents of change alongside elementary students; and (3) positioned themselves as science educators. We discussed the role of collaborative inquiry as a transformational pedagogical tool in teacher preparation programs.

While current Spanish dual-language immersion (DLI) programme models frequently promote strict adherence to structured Spanish and English times, we present an alternative approach, which frames children as language acquirers rather than as language learners. The approach, situated within a Spanish, DLI preschool, framed with a Reggio-inspired, developmentally appropriate framework for early childhood, counters deficit notions of emergent bilinguals, validates and affirms linguistic and cultural diversity, and provides spaces for young children to translanguage as they acquire first and second languages. In this study, we document the ways in which language is used in the space and how a first-year teacher's reflective practice evolves as she navigates pedagogical and identity shifts throughout her first year of implementation.

Teacher inquiry holds promise in teacher education, but only if student teachers take up inquiry practices as they leave preservice and transition to teaching. As they learn to conduct inquiry during preservice, student teachers may begin to internalize dispositions that promote ongoing inquiry experiences. Through analysis of questionnaires conducted at preservice and inservice, and through a focus group discussion, the authors sought to understand how teachers who had experienced one scaffolded, student-focused, and data-based preservice teacher inquiry model conceptualized the relationship between teaching and inquiry. Analyses revealed that teachers' conceptions cast inquiry overall as a tight fit with teaching in three ways: by fostering a focus on students, by generating metacognitive knowledge about inquiry as a useful classroom process, and by deepening teacher knowledge about ways to respond thoughtfully to diagnosed student need. Analyses suggest program model elements may have seeded these conceptions.

Consensus exists that effective teaching includes capacity to adapt instruction to respond to student learning challenges as they arise. Adaptive teachers may keep pace with rapidly evolving youth literacies and students' increasing cultural and linguistic diversity. Teachers are challenged to critically examine pedagogy when some contexts expect compliance with scripts and testing regimens and impede innovation. Recent research is building cumulative knowledge on adaptive teaching in literacy--its forms, purposes, and values. For preservice teachers (PSTs) still developing curriculum and routines, developing adaptive expertise is particularly challenging. The present study examined how, if at all, a data- based model of teacher inquiry in one teacher education program fostered adaptive teaching in grades 7-12 English language arts placements in mostly high poverty, highly diverse schools. The study examined 96 inquiries collected over seven years, plus PST questionnaires, memos, and discussions. PSTs overall worked with classroom data in ways that discerned patterns in student work and used findings to change the means by which their objectives could be met, through adapting literacy routines, materials, strategies, and activities. Adaptations were complex, not always effective, often challenging as PSTs weighed alternatives, tried to align adaptations with data, and worked to develop data-based rationales for instructional adaptations. Inquiry processes that supported PSTs in adaptive teaching included close examination of data, discovery and reflection, alignment of adaptations with data, and critique of adaptations. A disposition of flexibility supported the work. Findings contribute to literatures on adaptive literacy teaching and preservice teacher inquiry in English language arts.

Writing is central to academic development, permeates content area coursework and serves as both a vehicle for and a display of learning. For English learners (ELs), writing poses challenges, and teachers need preparation in how to understand and respond to these. This study reports 5 teacher inquiry processes that preservice teachers in one teacher education program used to learn more about their ELs and their writing performances, strengths, learning, preferences, and needs. The inquiry processes provided opportunities to develop knowledge of content and students (Ball, Thames, & Phelps, 2008), a key subdomain of the knowledge base of effective teaching.

Data literate educators can generate questions about learning in their classes; collect and analyze classroom data to answer them; and develop inferences and explanations. Two elements may promote data literacy: (a) breadth of classroom-based data collection and (b) depth of analysis. We examined these in inquiries conducted by 80 preservice teachers of secondary English in diverse classrooms over a 6-year period. Analyzing products, processes, and self-reports, we found inquiries evidenced a range in breadth of data collection and depth of analysis. Qualitative themes and two cases illustrate data analysis processes and challenges of pattern finding, initially crude analyses in striving for depth, and the need for data literacy mentoring. (Contains 1 table and 3 figures.)

The determinants of the temporal variability of indoor dust concentrations of semivolatile organic compounds (SVOCs) remain mostly unexplored. We examined temporal variability of dust concentrations and factors affecting dust concentrations for a wide range of SVOCs. We collected dust samples three times from 29 California homes during a period of 22 months and quantified concentrations of 47 SVOCs in 87 dust samples. We computed intraclass correlation coefficients (ICCs) using three samples collected within the same house. We calculated correlation coefficients (r) between two seasons with similar climate (spring and fall) and between two seasons with opposite climate (summer and winter). Among 26 compounds that were detected in more than 50% of the samples at all three visits, 20 compounds had ICCs above 0.50 and 6 compounds had ICCs below 0.50. For 19 out of 26 compounds, correlation coefficients between spring and fall (r = 0.48‐0.98) were higher than those between summer and winter (r = 0.09‐0.92), implying seasonal effects on dust concentrations. Our study showed that within‐home temporal variability of dust concentrations was small (ICC > 0.50) for most SVOCs, but dust concentrations may vary over time for some SVOCs with seasonal variations in source rates, such as product use. [ABSTRACT FROM AUTHOR]

Household dust is a reservoir of various consumer product chemicals. Thus, characterizing comprehensive chemical profiles of house dust may help improve our understanding of residential chemical exposure. We have previously developed a method for detecting a broad spectrum of chemicals in dust by applying a combination of target, suspect screening, and non‐target methods with mass spectrometry preceded by liquid chromatography and gas chromatography. Building upon a previous study that detected 271 compounds in 38 dust samples, we presented concentrations of 144 compounds that were confirmed and quantified by standards in the same set of samples. Ten compounds were measured with median concentrations greater than 10 000 ng/g of dust: cis‐hexadec‐6‐enoic acid, squalene, cholesterol, vitamin E, bis(2‐ethylhexyl) phthalate, dioctyl terephthalate, linoleic acid, tricaprylin, tris(1‐chloroisopropyl) phosphate, and oxybenzone. We also reviewed in vitro toxicity screening data to identify compounds that were not previously detected in indoor dust but have potential for adverse health effects. Among 119 newly detected compounds, 13 had endocrine‐disrupting potential and 7 had neurotoxic potential. Toxicity screening data were not available for eight biocides, which may adversely affect health. Our results strive to provide more comprehensive chemical profiles of house dust and identified information gaps for future health studies. [ABSTRACT FROM AUTHOR]

Background: The primary aim of this study was to investigate the effects of work rate, hydration status, and clothing on core body temperature (CBT) on California farmworkers. Methods: Two hundred and eighty‐seven farmworkers were recruited in Summer 2015, with 259 participants having sufficient data for analysis. We collected CBT, ambient temperature, work rate, body weight loss, and clothing worn by each participant throughout the work day and demographic data from a questionnaire. Results: Multiple regression with CBT as the outcome was used to determine the adjusted associations between CBT, environmental heat load, and worker characteristics. The multivariate regression model showed statistically significant associations of CBT with work rate (β = .006, 95% CI [0.004, 0.009]) and wet‐bulb globe temperature (β = .03, 95% CI [0.017, 0.05]). Conclusion: Results suggest that among our population workload is the primary modifiable risk factor for heat‐related illness. As expected, the ambient temperature was also associated with higher risk. [ABSTRACT FROM AUTHOR]

Farm workers are at risk of heat related illness (HRI), but their work rates that contribute to HRI have not been objectively assessed. The CHIPS study collected accelerometer data and characterized the physical activity of major farm tasks. Demographic information, work characteristics, and accelerometer data were collected from 575 farm workers in California. Each participating worker contributed measurements over one work shift. An Actical accelerometer was attached securely to a belt worn at the hip. Data were collected at one-minute intervals throughout the work shift. A total of 13 major work-task categories were defined. The mean physical activity counts per minute (cpm) and percentage of the shift spent at moderate and/or vigorous levels of activity were described for each task. Multiple linear regression models were constructed to determine the worker and environmental characteristics contributing to the physical activity level. Mean levels of physical activity ranged from 700 cpm (workers who carry produce) to a low of 150 cpm "ground pruners" who tend low-level plants, with an overall mean of 345 cpm or "light" activity (2 to ≤3 metabolic equivalents). The environmental temperature was the major factor associated with physical activity. A 10°C increase in the median temperature reduced the mean cpm by 135 (95% CI = 87, 193). Age and the tasks of sorting, ground pruning, and harvesting low-level crops were also negatively and independently associated with mean cpm. Incentivized (piece rate) pay, multi-task work, and irrigator work were positively associated with cpm. An interaction was found between piece rate and sex. Men's activity significantly increased (p < 0.001) by a mean of 95 cpm, (95% CI = 38.3, 150.7) if they were paid by the piece, but there was a non-significant association with women's activity level. Workers conducting multiple tasks, irrigators, men, and those earning incentivized (piece rate) pay had higher adjusted mean physical activity levels and are likely at increased risk of heat-related illness on hot days. [ABSTRACT FROM AUTHOR]

BACKGROUND: Maternal folic acid (FA) protects against developmental toxicity from certain environmental chemicals. OBJECTIVE: We examined combined exposures to maternal FA and pesticides in relation to autism spectrum disorder (ASD). METHODS: Participants were California children born from 2000-2007 who were enrolled in the Childhood Autism Risks from Genetics and the Environment (CHARGE) case-control study at age 2-5 y, were clinically confirmed to have ASD (n=296) or typical development (n=220), and had information on maternal supplemental FA and pesticide exposures. Maternal supplemental FA and household pesticide product use were retrospectively collected in telephone interviews from 2003-2011. High vs. low daily FA intake was dichotomized at 800 lg (median). Mothers' addresses were linked to a statewide database of commercial applications to estimate agricultural pesticide exposure. RESULTS: High FA intake (≥800 lg) during the first pregnancy month and no known pesticide exposure was the reference group for all analyses. Compared with this group, ASD was increased in association with <800 lg FA and any indoor pesticide exposure {adjusted odds ratio [OR]=2:5 [95% confidence interval (CI): 1.3, 4.7]} compared with low FA [OR=1:2 (95% CI: 0.7, 2.2)] or indoor pesticides [OR =1:7 (95% CI: 1.1, 2.8)] alone. ORs for the combination of low FA and regular pregnancy exposure (≥6 mo) to pet pesticides or to outdoor sprays and foggers were 3.9 (95% CI: 1.4, 11.5) and 4.1 (95% CI: 1.7, 10.1), respectively. ORs for low maternal FA and agricultural pesticide exposure 3 mo before or after conception were 2.2 (95% CI: 0.7, 6.5) for chlorpyrifos, 2.3 (95% CI: 0.98, 5.3) for organophosphates, 2.1 (95% CI: 0.9, 4.8) for pyrethroids, and 1.5 (95% CI: 0.5, 4.8) for carbamates. Except for carbamates, these ORs were approximately two times greater than those for either exposure alone or for the expected ORs for combined exposures under multiplicative or additive models. CONCLUSIONS: In this study population, associations between pesticide exposures and ASD were attenuated among those with high versus low FA intake during the first month of pregnancy. Confirmatory and mechanistic studies are needed. [ABSTRACT FROM AUTHOR]

Background: Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in many household items. Given concerns over their potential adverse health effects, we identified predictors and evaluated temporal changes of PBDE serum concentrations. Methods: PBDE serum concentrations were measured in young children (2-8 years old; N = 67), parents of young children (<55 years old; N = 90), and older adults (≥55 years old; N = 59) in California, with concurrent floor wipe samples collected in participants' homes in 2008-2009. We also measured serum concentrations one year later in a subset of children (N = 19) and parents (N = 42). Results: PBDE serum concentrations in children were significantly higher than in adults. Floor wipe concentration is a significant predictor of serum BDE-47, 99,100 and 154. Positive associations were observed between the intake frequency of canned meat and serum concentrations of BDE-47, 99 and 154, between canned meat entrees and BDE-154 and 209, as well as between tuna and white fish and BDE-153. The model with the floor wipe concentration and food intake frequencies explained up to 40% of the mean square prediction error of some congeners. Lower home values and renting (vs. owning) a home were associated with higher serum concentrations of BDE-47, 99 and 100. Serum concentrations measured one year apart were strongly correlated as expected (r = 0.70-0.97) with a slight decreasing trend. Conclusions: Floor wipe concentration, food intake frequency, and housing characteristics can explain 12-40% of the prediction error of PBDE serum concentrations. Decreasing temporal trends should be considered when characterizing long-term exposure. [ABSTRACT FROM AUTHOR]

Perfluorinated compounds (PFCs) have been widely used in industrial applications and consumer products. Their persistent nature and potential health impacts are of concern. Given the high cost of collecting serum samples, this study is to understand whether we can quantify PFC serum concentrations using factors extracted from questionnaire responses and indirect measurements, and whether a single serum measurement can be used to classify an individual′s exposure over a one-year period. The study population included three demographic groups: young children (2–8 years old) ( N =67), parents of young children (<55 years old) ( N =90), and older adults (>55 years old) ( N =59). PFC serum concentrations, house dust concentrations, and questionnaires were collected. The geometric mean of perfluorooctane sulfonic acid (PFOS) was highest for the older adults. In contrast, the geometric mean of perfluorooctanoic acid (PFOA) was highest for children. Serum concentrations of the parent and the child from the same family were moderately correlated (Spearman correlation ( r )=0.26–0.79, p <0.05), indicating common sources within a family. For adults, age, having occupational exposure or having used fire extinguisher, frequencies of consuming butter/margarine, pork, canned meat entrées, tuna and white fish, freshwater fish, and whether they ate microwave popcorn were significantly positively associated with serum concentrations of individual PFCs. For children, residential dust concentrations, frequency of wearing waterproof clothes, frequency of having canned fish, hotdogs, chicken nuggets, French fries, and chips, and whether they ate microwave popcorn were significant positive predictors of individual PFC serum concentrations. In addition, the serum concentrations collected in a subset of young children ( N =20) and the parents ( N =42) one year later were strongly correlated ( r =0.68–0.98, p <0.001) with the levels measured at the first visits, but showed a decreasing trend. Children had moderate correlation ( r =0.43) between serum and dust concentrations of PFOS, indicating indoor sources contribute to exposure. In conclusion, besides food intake, occupational exposure, consumer product use, and exposure to residential dust contribute to PFC exposure. The downward temporal trend of serum concentrations reflects the reduction of PFCs use in recent years while the year-to-year correlation indicates that a single serum measurement could be an estimate of exposure relative to the population for a one-year period in epidemiology studies. [ABSTRACT FROM AUTHOR]

Despite California's dependence on hired farm labor, scarce research has been conducted on the respiratory health of hired farm workers. Agricultural exposures to inorganic and organic dusts can adversely affect an individual's respiratory health and differ by farm type and job task. The purpose of the present analysis was to examine associations between agricultural work exposures and pulmonary function among 450 California farm workers. Data were collected as part of the Mexican Immigration to California: Agricultural Safety and Acculturation (MICASA) study, a prospective cohort study examining occupational risk factors and health of hired farm worker families in Mendota, California. Time-weighted self-reported average (TWSRA) dust scores were calculated from assessments of past-12-month agricultural work history. Other dust exposure indicator variables included months worked in agriculture in the past 12 months and years worked in agriculture. Multiple linear regression modeled FEV1 (forced expiratory volume in 1 second), FEF25–75% (forced midexpiratory flow rate), FVC (forced vital capacity), FEV6, FEV1/FVC, and FEV1/FEV6 separately. Seventy-six percent of participants had worked in agriculture in the past year. In models conducted for crops and tasks separately, high TWSRA dust score was associated with better FEV6. Crop and task models showed associations between greater months worked in agriculture in the past year and better FEV1, FEF25–75%, and FEV6. Both models also found greater years worked in agriculture to be associated with worse FEV1/FEV6. Results were generally in the opposite direction as expected given past research but not uncommon. Future research should investigate relationships between pulmonary function and agricultural dust exposure over a lifetime and changes in pulmonary function over time. [ABSTRACT FROM AUTHOR]

The article offers research on a study related to the influence of region of birth and sex on agricultural work and use of protective measures in the immigrant Latino farm workers in Mendota, California. It mentions the preventive measures to avoid agricultural injuries including educational models for cultural factors, employer engagement, and use of community health workers. It also informs that the study involved measurement of demographic characteristics.

Abstract: Agricultural work is a major contributor to California's and the nation's economy and employs a large number of workers. However, agricultural work can have numerous risks, such as exposure to elevated levels of particulate matter (PM) and other airborne pollutants with potential adverse health effects. To determine the magnitude of occupational exposures, PM levels were assessed for 89 workers from three major crops in California; almonds, melons and tomatoes. Personal samples were collected for PM2.5 and inhalable PM using personal sampling equipment. Geometric mean concentrations from personal exposure for workers in almonds (inhalable PM=4368μg/m3, PM2.5 =122μg/m3, N =5), tomatoes (inhalable PM=1410μg/m3, PM2.5 =12μg/m3, N =33), and melons (inhalable PM=1118μg/m3, PM2.5 =19μg/m3, N =51) showed high PM exposure when working with these three crops. Large exposure differences by crop were more common than by task (i.e. harvesting, packing and weeding) among the three crops studied. This is the largest study of agricultural workers engaged in hand harvesting, a significant employer of farm labor, and relatively high levels of exposure to PM were measured. [Copyright &y& Elsevier]

Abstract: Occupational exposure of dairy workers to particulate matter (PM) and endotoxin has been considered by some to be of potential concern. This paper reports personal exposure concentrations of PM (μg/m3) and endotoxin (EU/m3) for 226 workers from 13 California dairies. Arithmetic mean personal concentrations for PM2.5, inhalable PM and endotoxin were 48μg/m3 (N =222), 987μg/m3 (N =225) and 453EU/m3 (N =225), respectively. Using mixed effects models, time spent re-bedding of freestall barns versus any other job conducted on a dairy led to the highest exposure for PM2.5, inhalable PM, and endotoxin. Personal exposure concentrations were found to be greater than those reported for ambient area based concentrations at the same dairies. A pseudo R-square approach revealed that one area based measure combined with time spent performing tasks explained a significant portion of variation in personal exposure concentrations. [Copyright &y& Elsevier]

Over the past 30 yr, individual California dairy operations have grown in size; however, little is known about the distribution and determinants of particulate matter (PM) concentrations on these dairies. Elevated exposure to PM is associated with respiratory and cardiovascular health effects, particularly in occupational settings. The purpose of this study was to quantify the concentrations of PM2.5 and all inhalable PM (0–100 µm) on California dairies. Samplers were placed at various locations (e.g., milking parlor, grain storage area, drylot corral, and freestall barns) on 13 different dairies to collect PM2.5 and all inhalable PM during the 2008 summer months. The PM2.5 and all inhalable PM concentrations varied between different areas on a dairy and from dairy to dairy. Geometric mean concentrations for PM2.5 and inhalable PM were 24 µg m−3 (range, 2–116 µg m−3) and 332 μg m−3 (range, 74–1690 µg m−3). A key variable for explaining variation in PM2.5 concentrations with a mixed effects model was regional background ambient concentrations of PM2.5. No significant differences were observed in mean concentrations between upwind and downwind fence line concentrations (adjusted geometric mean ratio [AGMR] = 0.7; 95% CI, 0.4–1.3), although significant differences were found between upwind and central location mean values (AGMR = 0.5; 95% CI, 0.3–0.8; p < 0.01). These results indicate dairy PM sources and, thus, elevated occupational exposure. Covariates, such as the age of the dairy and number of cows in the freestall barn and drylot corral, were important variables in explaining PM concentration variability. Levels of PM were lower compared with dairies in other U.S. states and other countries. [ABSTRACT FROM AUTHOR]

Objectives Despite increasing availability of global positioning system (GPS), no research has been conducted to analyze GPS data for exposure opportunities associated with time at indoor and outdoor microenvironments. We developed location-based and time-weighted spatial measures that incorporate indoor and outdoor time-location data collected by GPS. Methods Time-location data were drawn from 38 female subjects in California who wore a GPS device for seven days. Ambient standard deviational ellipse was determined based on outdoor locations and time duration, while indoor time weighted standard deviational ellipse (SDE) was developed to incorporate indoor and outdoor times and locations data into the ellipse measure. Results Our findings indicated that there was considerable difference in the sizes of exposure potential measures when indoor time was taken into consideration, and that they were associated with day type (weekday/weekend) and employment status. Conclusions This study provides evidence that time-location weighted measure may provide better accuracy in assessing exposure opportunities at different microenvironments. The use of GPS likely improves the geographical details and accuracy of time-location data, and further development of such location-time weighted spatial measure is encouraged. [ABSTRACT FROM AUTHOR]

Traditionally, use of household and personal care products has been collected through questionnaires, which is very time consuming, a burden on participants, and prone to recall bias. As part of the SUPERB Project (Study of Use of Products and Exposure-Related Behaviors), a novel platform was developed using bar codes to quickly and reliably determine what household and personal care products people have in their homes and determine the amount used over a 1-week period. We evaluated the acceptability and feasibility of our methodology in a longitudinal field study that included 47 California households, 30 with young children and 17 with an older adult. Acceptability was defined by refusal rates; feasibility was evaluated in terms of readable bar codes, useful product information in our database for all readable barcodes, and ability to find containers at both the start and end of the week. We found 63% of personal care products and 87% of the household care products had readable barcodes with 47% and 41% having sufficient data for product identification, respectively and secondly, the amount used could be determined most of the time. We present distributions for amount used by product category and compare inter- and intra-person variability. In summary, our method appears to be appropriate, acceptable, and useful for gathering information related to potential exposures stemming from the use of personal and household care products. A very low drop-out rate suggests that this methodology can be useful in longitudinal studies of exposure to household and personal care products. [ABSTRACT FROM AUTHOR]

Abstract: Given the concern over the potential for health risks associated with certain ingredients (e.g., phthalates) in personal care products, usage patterns of ∼30 types of personal care products (e.g., shampoo, sunscreen, fragrance, etc.) were collected in 604 California households through a telephone interview. Preferences in selecting products, e.g., scented or unscented, aerosol, and brand loyalty, were also investigated. Participants were recruited in three age groups, children (mostly preschoolers), their parents, and adults age 55 or older. Use frequencies of various product types varied by sex, age group, race, education, and climatic region. Product use by parent and child from the same household were correlated. Use frequencies of products in the same class (e.g., skincare) were moderately correlated, which may impact aggregate exposures. Use frequencies observed in this study were generally in the same range as those reported in the EPA Exposure Factor Handbook, but we found differences for some individual products. Our study provides additional data on population-based usage patterns of a large collection of commonly used personal care products pertaining to several age groups and socio-demographic strata. This information will be valuable for exposure and risk assessments. [ABSTRACT FROM AUTHOR]

Two-week average concentrations of ozone (O3), nitric acid vapor (HNO3) and ammonia (NH3) were measured with passive samplers during the 2002 summer season across the central Sierra Nevada Mountains, California, along the San Joaquin River drainage. Elevated concentrations of the pollutants were determined with seasonal means for individual sites ranging between 62 and 88 ppb for O3, 1.0–3.8 μg m−3 for HNO3, and 2.6–5.2 μg m−3 for NH3. Calculated O3 exposure indices were very high, reaching SUM00-191 ppm h, SUM60-151 ppm h, and W126-124 ppm h. Calculated nitrogen (N) dry deposition ranged from 1.4 to 15 kg N ha−1 for maximum values, and 0.4–8 kg N ha−1 for minimum values; potentially exceeding Critical Loads (CL) for nutritional N. The U.S., California, and European 8 h O3 human health standards were exceeded during 104, 108, and 114 days respectively, indicating high risk to humans from ambient O3. [Copyright &y& Elsevier]

This study determined the body burden of PBDEs in 100 California children, and evaluated associations with sociodemographic, household, and dietary factors. In national and international comparisons, California dust, breast milk, and human serum samples contain higher concentrations of PBDEs. Higher levels in children suggest exposure pathways depend upon age. Plasma samples were analyzed for PBDEs using GC/MS. Circulating levels of PBDEs were 10-to 1000-fold higher than similar aged populations in Mexico and Europe, 5-times higher than similar aged children across the U.S., and 2- to 10-fold higher than U.S. adults. Increased levels of higher-brominated congeners were associated with the recent purchase of new upholstered furniture or mattresses and consumption of pork. Concentrations of lower-brominated congeners increased with frequency of poultry consumption. Lower maternal education was independently and significantly associated with higher levels of most congeners in the children. [ABSTRACT FROM AUTHOR]

Background: Exposure to toxic chemicals in the home is a growing concern. This report presents an overview of the recruitment, methods for data collection, instruments used to collect data, and participant demographics for a study examining behaviors that influence exposure to environmental toxins in the home environment, also known as SUPERB (Study of Use of Products and Exposure Related Behaviors). Methods: The methods involved three different platforms: telephone interviews, internet-based surveys, and home-based monitoring. The purposes of SUPERB were: first, to compare data collection platforms with regard to feasibility, acceptability and reliability; and second, to provide longitudinal population-based data characterizing seasonal and long-term changes in exposure-related behaviors including food consumption, temporal-spatial activity, and household product use. Results: Two cohorts of households were enrolled: families (one parent and one child) from northern California and older individuals (age 55+) from central California. Parents (n = 499) in Northern California families were on average 36 years of age, 47.1% were Latino or nonwhite, and 10.2% took the survey in Spanish. Most of the children enrolled (n = 566) were under 6 years (82.7%). The older adults enrolled (n = 156) were, on average, 66 years of age and 23.7% were Latino or nonwhite, but only 2.6% completed the survey in Spanish. Conclusions: We found that oversampling was successful in improving recruitment of under-represented subgroups, such as those with low education, thereby increasing diversity of our study sample. Protocols that minimize participant time, e.g., use of bar scanners and scales rather than questionnaires regarding use of household products, and the implementation of these protocols by staff who built relationships of trust, resulted in high retention over a longitudinal data collection scheme. A relatively small fraction of those who volunteer for longitudinal internet surveys are consistent in filling them out. Future reports will provide critical information on cross-sectional, seasonal and longitudinal patterns of exposure related behaviors in young children, parents of young children, and older adults. [ABSTRACT FROM AUTHOR]

Acrolein, a volatile, unsaturated aldehyde, is a known respiratory toxicant and one of the 188 most hazardous air pollutants identified by the U.S. EPA. A newly developed analytical method was used to determine residential indoor air concentrations of acrolein and other volatile aldehydes in nine homes located in three California counties (Los Angeles, Placer, Yolo). Average indoor air concentrations of acrolein were an order of magnitude higher than outdoor concentrations at the same time. All homes showed similar diurnal patterns in indoor air concentrations, with acrolein levels in evening samples up to 2.5 times higher than morning samples. These increases were strongly correlated with temperature and cooking events, and homes with frequent, regular cooking activity had the highest baseline (morning) acrolein levels. High acrolein concentrations were also found in newly built, uninhabited homes and in emissions from lumber commonly used in home construction, suggesting indoor contributions from off-gassing and/or secondary formation. The results provide strong evidence that human exposure to acrolein is dominated by indoor air with little contribution from ambient outdoor air. [ABSTRACT FROM AUTHOR]

Human exposure to per- and polyfluoroalkyl substances (PFAS) has changed since the early 2000s, in part, because of the phase-out and replacement of some long-chain PFAS. Studies of PFAS exposure and its temporal changes have been limited to date mostly to adults and pregnant women. We examined temporal trends and determinants of PFAS serum concentrations among mothers with a young child who participated in the CHARGE ( CH ildhood A utism R isk from G enetics and E nvironment) case-control study. We quantified nine PFAS in serum samples collected from 2009 to 2016 in 450 Northern California mothers when their child was 2–5 years old. With five compounds that were detected in more than 50% of the samples, we performed multiple regression to estimate least square geometric means (LSGMs) of PFAS concentrations with adjustment for sampling year and other characteristics that may affect maternal concentrations (e.g., breastfeeding duration). We also used time-related regression coefficients to calculate percent changes over the study period. LSGM concentrations of perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS), and perfluorohexane sulfonate (PFHxS) decreased over the study period [percent change (95% confidence interval): −10.7% (−12.7%, −8.7%); −10.8% (−12.9%, −8.5%); −8.0% (−10.5%, −5.5%), respectively]. On the other hand, perfluorononanoate (PFNA) and perfluorodecanoate (PFDA) showed mixed time trends. Among the selected covariates, longer breastfeeding duration was associated with decreased maternal serum concentrations of PFOA, PFOS, PFHxS, PFNA and PFDA. Our study demonstrated that body burden of some common long-chain PFAS among California mothers with a young child decreased over the study period and that breastfeeding appears to contribute to the elimination of PFAS in lactating mothers. • PFOA, PFOS, PFHxS, and Me-FOSAA monotonically decreased during the study period. • PFNA, PFDeA and PFUA exhibited mixed trends. • Breastfeeding contributed to the elimination of the common PFAS in lactating mothers. • Our study participants had lower PFAS serum concentrations than NHANES participants. [ABSTRACT FROM AUTHOR]

Smoke from wildfires can expose individuals and populations to elevated levels of particulate matter (PM) and ozone (O[sub 3] ). Between 21 July and 26 August 2002, the McNally Fire burned over 150 000 acres (61 000 ha). The fire occurred in the Sequoia National Forest, in the southern Sierra Nevada of California. This study evaluated the effects of the McNally Fire on air quality, specifically particles <10 μm in diameter (PM[sub 10] ) and O[sub 3] . Downwind of the fire on the eastern side of the Sierra Nevada, 24-h concentrations of PM[sub 10] more than doubled. The PM[sub 10] federal standard was exceeded four times during the fire. Violations of the California PM[sub 10] standard increased drastically during the fire. The California PM[sub 10] standard was violated six times before the fire and 164 times during the fire. Most of the PM[sub 10] exceedances occurred at the Kernville Work Center and sites east of the fire. Compared with the other sites, the highest 2-week average O[sub 3] concentrations occurred in the eastern part of the Sierra Nevada and north of the fire, where O[sub 3] increased by a factor of two at two locations. There are possible negative effects on human health caused by large wildfires on communities near and downwind of the fire, particularly when more than 2000 acres (809 ha) are burned per day. Most of the PM[sub 10] exceedances occurred at sites closest to and east of the fire, none in the San Joaquin Valley. The highest 2-week average O[sub 3] concentrations occurred in the eastern part of the Sierra Nevada and north of the fire. Large fire size and high fire intensity in combination with urban pollutants from the Central Valley may be the leading cause of increased concentrations of ozone and particulate matter in rural mountain communities of the Sierra Nevada. [ABSTRACT FROM AUTHOR]

This field study of 37 small and medium commercial buildings throughout California obtained information on ventilation rate, temperature, and heating, ventilating, and air-conditioning (HVAC) system characteristics. The study included seven retail establishments; five restaurants; eight offices; two each of gas stations, hair salons, healthcare facilities, grocery stores, dental offices, and fitness centers; and five other buildings. Fourteen (38%) of the buildings either could not or did not provide outdoor air through the HVAC system. The air exchange rate averaged 1.6 (s.d. = 1.7) exchanges per hour and was similar between buildings with and without outdoor air supplied through the HVAC system, indicating that some buildings have significant leakage or ventilation through open windows and doors. Not all buildings had sufficient air exchange to meet ASHRAE 62.1 Standards, including buildings used for fitness centers, hair salons, offices, and retail establishments. The majority of the time, buildings were within the ASHRAE temperature comfort range. Offices were frequently overcooled in the summer. All of the buildings had filters, but over half the buildings had a filter with a minimum efficiency reporting value rating of 4 or lower, which are not very effective for removing fine particles. Practical Implications Most U.S. commercial buildings (96%) are small- to medium-sized, using nearly 18% of the country's energy, and sheltering a large population daily. Little is known about the ventilation systems in these buildings. This study found a wide variety of ventilation conditions, with many buildings failing to meet relevant ventilation standards. Regulators may want to consider implementing more complete building inspections at commissioning and point of sale. [ABSTRACT FROM AUTHOR]

This study monitored indoor and outdoor particle concentrations in 37 small and medium commercial buildings (SMCBs) in California with three buildings sampled on two occasions, resulting in 40 sampling days. Sampled buildings included offices, retail establishments, restaurants, dental offices, and hair salons, among others. Continuous measurements were made for both ultrafine and fine particulate matter as well as black carbon inside and outside of the building. Integrated PM2.5, PM2.5-10, and PM10 samples were also collected inside and outside the building. The majority of the buildings had indoor/outdoor (I/O) particle concentration ratios less than 1.0, indicating that contributions from indoor sources are less than removal of outdoor particles. However, some of the buildings had I/O ratios greater than 1, indicating significant indoor particle sources. This was particularly true of restaurants, hair salons, and dental offices. The infiltration factor was estimated from a regression analysis of indoor and outdoor concentrations for each particle size fraction, finding lower values for ultrafine and coarse particles than for submicrometer particles, as expected. The I/O ratio of black carbon was used as a relative measure of the infiltration factor of particles among buildings, with a geometric mean of 0.62. The contribution of indoor sources to indoor particle levels was estimated for each building. [ABSTRACT FROM AUTHOR]

Objective: Determine compliance with and effectiveness of California regulations in reducing farmworkers' heat-related illness (HRI) risk and identify main factors contributing to HRI. Methods: In a cross-sectional study of Latino farmworkers, core body temperature (CBT), work rate, and environmental temperature (WBGT) were monitored over a work shift by individual ingestible thermistors, accelerometers, and weather stations, respectively. Multiple logistic modeling was used to identify risk factors for elevated CBT. Results: Although farms complied with Cal/OSHA regulations, worker training of HRI prevention and hydration replacement rates were insufficient. In modeling (AOR [95% CI]) male sex (3.74 [1.22 - 11.54]), WBGT (1.22 [1.08 - 1.38]), work rate (1.004 [1.002 - 1.006]), and increased BMI (1.11 [1.10 - 1.29]) were all independently associated with elevated CBT. Conclusion: Risk of HRI was exacerbated by work rate and environmental temperature despite farms following Cal/OSHA regulations. [ABSTRACT FROM AUTHOR]

Presents information on a study which compared the predicted influence of dairy cattle farming with the predicted influence of the human population on the nitrogen budget of a rural watershed in Marin County, California. Site description; Model structure and methodology; Overview on cattle-waste management; Conclusions.

Objective: The California heat illness prevention study (CHIPS) devised methodology and collected physiological data to assess heat related illness (HRI) risk in Latino farmworkers. Methods: Bilingual researchers monitored HRI across a workshift, recording core temperature, work rate (metabolic equivalents [METs]), and heart rate at minute intervals. Hydration status was assessed by changes in weight and blood osmolality. Personal data loggers and a weather station measured exposure to heat. Interviewer administered questionnaires were used to collect demographic and occupational information. Results: California farmworkers (n = 588) were assessed. Acceptable quality data was obtained from 80% of participants (core temperature) to 100% of participants (weight change).Workers (8.3%) experienced a core body temperature more than or equal to 38.5 °C and 11.8% experienced dehydration (lost more than 1.5% of body weight). Conclusions: Methodology is presented for the first comprehensive physiological assessment of HRI risk in California farmworkers. [ABSTRACT FROM AUTHOR]

Objective: To assess respiratory exposures and lung function in a crosssectional study of California dairy workers. Methods: Exposure o f 205 dairy and 45 control (vegetable processing) workers to particulate matter and endotoxin was monitored. Pre- and postshift spirometry and interviews were conducted. Results: Geometric mean inhalable and PM2.5 concentrations were 812 and 35.3 jug/m3 versus 481.9 and 19.6 /rg/m3, respectively, for dairy and control workers. Endotoxin concentrations were 329 EU/m3 or 1122 pmol/m3 and 13.5 EU/m3 or 110 pmol/m3, respectively, for dairy and control workers. In a mixed-effects model, forced vital capacity decreased across a work shift by 24.5 mL (95% confidence interval, -4 4 .7 to -4 .3 ; P = 0.018) with log 10 (total endotoxin) and by 22.0 mL (95% confidence interval, —43.2 to — 0.08; P = 0.042) per hour worked. Conclusions: Modern California dairy endotoxin exposures and shift length were associated with a mild acute decrease in forced vital capacity. [ABSTRACT FROM AUTHOR]

The article focuses on a study conducted to determine that dairy workers in California have lower baseline and greater cross shift decrements in lung functions than control employees. A mixed effects multiple linear regression modeling strategy was used on people in mid thirties and revealed that dairy workers experienced a greater cross shift decrement due to the exposure with airway obstruction. It advises that asthama and asthama like symptoms should be further researched.

While small- and medium-sized commercial buildings (SMCBs) make up 96% of the commercial buildings in the U.S., serving a large variety of uses, little information is available on indoor air quality (IAQ) in SMCBs. This study investigated 37 SMCBs distributed across different sizes, ages, uses, and regions of California. We report indoor concentrations and whole building emission rates of a suite of 30 VOCs and aldehydes in these buildings. There was a considerable range in the concentrations for each of the contaminants, especially for formaldehyde, acetaldehyde, decamethylcyclopentasiloxane, d-limonene, 2-butoxyethanol, toluene, 2,2,4-trimethylpentanediol diisobutyrate, and diethylphthalate. The cause of higher concentrations in some building categories generally corresponded to expected sources, for example, chloroform was higher in restaurants and grocery stores, and formaldehyde was higher in retail stores and offices. Factor analysis suggests sources in SMCBs include automobile/traffic, cleaning products, occupant sources, wood products/coating, and plasticizers. The comparison to health guidelines showed that formaldehyde concentrations were above the chronic RELs required by the OEHHA (9 μg/m3) in 86% of the buildings. Data collected in this study begins to fill the knowledge gap for IAQ in SMCBs and helps us understand the indoor sources of VOCs to further improve indoor air quality in SMCBs. [ABSTRACT FROM AUTHOR]

Polyurethane foam (PUF), a proven sampling medium for measuring air concentrations of organic compounds, is widely used in upholstered home furniture. We evaluated the potential utility of couch PUF as a passive sampler and as a reservoir for non-flame retardant semivolatile organic compounds (SVOCs). We collected PUF samples from 13 California home couches, measured concentrations (C PUF) of 64 SVOCs at three different depths (i.e., top, top-middle, and middle from couch surfaces facing outward), and examined concentration changes with depth. To calculate the PUF-air partition coefficient (K PUF-air = C PUF / C air = C PUF × K dust-air / C dust), we used the calculated dust-air partition coefficient (K dust-air) with the octanol-air partition coefficient (K oa) and dust concentrations (C dust) simultaneously collected and measured. We used K PUF-air to compute fugacity capacity of PUF and chemical mass distribution among various indoor compartments and PUF. Among 29 detected compounds, 11 compounds were detected in more than 50% of the samples at all depths. Among the 11 compounds, concentrations of phenanthrene, 2-benzylideneoctanal, galaxolide, tonalide, and homosalate decreased with depth. Among the studied SVOCs, more than 20% of the total mass was distributed to couch PUF for phenol and compounds in skin-applied products (i.e., 2-benzylideoneoctanal, galaxolide, and homosalate). Our results showed that couch PUF can absorb many SVOCs and may be an important reservoir for some SVOCs. However, it may not be an effective passive sampling medium for those that have relatively high K oa values. Direct dermal contact with couch seats may be an important exposure route for non-users of skin-applied compounds. [Display omitted] • Measured concentrations of 64 SVOCs in couch PUF samples at varying depths. • Detection frequency was the highest at the top section for most detected compounds. • Observed difference and similarity in K PUF-air between upholstered PUF and bare PUF. • Couch PUF may be an important reservoir for some compounds. • Dermal contact with couch seats may be an important exposure route for skin-applied compounds. [ABSTRACT FROM AUTHOR]