Malodor as a trigger of stress and negative mood in neighbors of industrial hog operations

Olfactometric and Chemical Characterisation of Gaseous Emission from Crude Oils

This study focuses on the olfactometric and chemical characterisation of gaseous and vapour emissions from different crude oils. To investigate this topic, laboratory experiments were set up to obtain comparable gaseous samples: they were estimated in terms of odour concentration (Cod), via dynamic olfactometry, and chemical-specific characterisation. It was found that, even if considered similar in regard to physical properties and chemical composition, the gaseous emissions of different crude oils are significantly different in terms of odorous potential. The observed discrepancy appears to be associated with the presence of volatile organic sulphur compounds (VOSCs), and the highest values of Cod were found in samples containing mercaptans and sulphides. In addition, from the conducted comparison, it appeared that crude odorous potential, in terms of Cod, is not strictly linked to the quantity of the volatile organic compounds (VOCs), H2S concentration, or a priori knowledge of the percentage of elemental sulphur in the crude; on the contrary, the presence of volatile organic sulphur compounds in the gaseous emissions is the most influential parameter for the odour potential of this matrix.

Satellite Observations of Atmospheric Ammonia Inequalities Associated with Industrialized Swine Facilities in Eastern North Carolina

Industrialized swine facilities adversely affect the health and well-being of Eastern North Carolina residents in the U.S. and are an issue of environmental racism. Concentrated animal feeding operations (CAFOs) emit various harmful and noxious air pollutants, including ammonia (NH3). There are limited measurements of CAFO-related air quality, contributing to disputes around its severity. We use NH3 vertical column densities from the space-based Infrared Atmospheric Sounding Interferometer (IASI) to report systematic, distributive inequalities in NH3 column enhancements (ΔNH3 columns), equal to NH3 columns less an observationally determined tropospheric background. Population-weighted block group-scale ΔNH3 columns are higher by 27 ± 3% for Black and African Americans, 35 ± 3% for Hispanics and Latinos, and 49 ± 3% for American Indians compared to non-Hispanic/Latino whites in Eastern North Carolina (April-August 2016-2021). Surface winds and air temperature influence block group-scale NH3 distributions, with higher absolute NH3 inequalities for all groups on calm days and for Black and African Americans and Hispanics and Latinos on hot days, consistent with effects from NH3 volatization downfield of facilities from, e.g., manure-covered fields, particles, and other surfaces. ΔNH3 columns correspond spatially with permitted swine facilities, with residents living multiple kilometers from swine CAFOs chronically exposed to elevated NH3. Trends in NH3 columns over 2008-2023 are driven by regional-scale atmospheric processes rather than localized NH3 changes in CAFO emissions. Results are discussed in local decision-making contexts that have broad relevance for air quality issues without protective federal regulatory standards.

Distance and Direction Matters: Risk Perception Among Residents Around a Dump Yard in Kerala, India

Purpose

Waste mismanagement is a growing concern in developing countries where unsustainable practices such as open dumping and open burning are rampant. This study examined the risk perceptions of the residents living in proximity to the Brahmapuram dump yard, situated in Ernakulam district of Kerala State, India- A site marked by persistent local protests, public outrage, and legal disputes arising from issues related to waste mismanagement. The study focused on the geospatial and sociodemographic factors that might influence these perceptions.

Patients and Methods

A cross-sectional survey was conducted among 302 respondents living within 4 kilometers from the borders of the dump yard using a structured interview schedule. The responses of the participants were used to compute a risk perception score, which reflected participants' risk perception regarding the environment and their health.

Results

Among the participants in the study, those who lived within 2 kilometers (2.3 (95% CI 0.96, 3.7; p<0.001)), those who lived to the east (2.7 (95% CI 1.1, 4.2; p<0.001)) and those who reported perceiving strong malodor from the dump yard (2.0 (95% CI 0.54, 3.4; p=0.007)), had a higher risk perception in the multivariate linear regression model. Women had a lesser risk perception compared to men (-2.6 (95% CI -3.7, -1.4; p<0.001)).

Conclusion

The findings highlight the importance of geospatial characteristics (distance and direction), malodor and gender differences in shaping the risk perceptions among the proximate residents living around a waste dump yard. Consideration of geospatial and sociodemographic determinants in risk assessment and management could potentially reduce the perceived risks and public discontent around waste management facilities.

Does air pollution fuel irrational behaviors in stock investments?

This paper investigates the influence of air pollution on irrational behaviors in stock trading through behavioral experiments in laboratory, simulating air pollution by burning straw and mosquito coils. The results of this study show that air pollution significantly improves disposition effect and repurchase effect in an asymmetric way, which are thought as irrational behaviors in stock investments, making subjects prefer selling winning stocks (part of disposition effect) and repurchasing stocks that have fallen in price since the sale (part of repurchase effect). Furthermore, regret, a negative emotion, is the psychological mechanism by which air pollution influences the irrational behaviors.

Effects of the Molecular Structure of Malodor Substances and Their Masking on 1,2-Dioleoyl-sn-glycero-3-phosphocholine Molecular Layers

Certain odors have been shown not only to cause health problems and stress but also to affect skin barrier function. Therefore, it is important to understand olfactory masking to develop effective fragrances to mask malodors. However, olfaction and olfactory masking mechanisms are not yet fully understood. To understand the mechanism of the masking effect that has been studied, the responses of several target substance (TS) molecules-1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) mixed molecular layers to odorant (OD) molecules were examined as a simple experimental model of epithelial cellular membranes injured by TS molecules. Here, we examined trans-2-nonenal, 1-nonanal, trans-2-decenal, and 1-decanal as TS molecules to clarify the effects of double bonds and hydrocarbon chain lengths on the phospholipid molecular layer. In addition, benzaldehyde and cyclohexanecarboxaldehyde were utilized as OD molecules to clarify the masking effect of the aromatic ring. Surface pressure (Π)-area (A) isotherms were measured to clarify the adsorption or desorption of TS and OD molecules on the DOPC molecular layer. In addition, Fourier transform infrared spectroscopy was performed to clarify the interactions among DOPC, TS, and OD molecules. We found that TS molecules with and without double bonds had different effects on the DOPC molecular layer and that molecules with shorter chain lengths had greater effects on the DOPC molecular layer. Furthermore, OD molecules with aromatic rings counteracted the effects of the TS molecules. On the basis of this research, not only a detailed mechanism by which odor molecules affect lipid membranes without mediating olfactory receptors is elucidated but also more effective OD molecules with masking effects are proposed.

Residents' experiences during a hydrogen sulfide crisis in Carson, California

BACKGROUND

In early October 2021, thousands of residents in Carson, California began complaining of malodors and headaches. Hydrogen sulfide (H2S), a noxious odorous gas, was measured at concentrations up to 7000 parts per billion (ppb) and remained above California's acute air quality standard of 30 ppb for a month. Intermittent elevations of H2S continued for 3 months. After 2 months of malodor in this environmental justice community, a government agency attributed the H2S to environmental pollution from a warehouse fire. Research has yielded conflicting results on the health effects of H2S exposure at levels that were experienced during this event. This research fills a critical need for understanding how people perceive and experience emergent environmental health events and will help shape future responses.

METHODS

Through a community-academic partnership, we conducted 6 focus groups with 33 participants who resided in the Carson area during the crisis. We sought to understand how this incident affected residents through facilitated discussion on topics including information acquisition, impressions of the emergency response, health symptoms, and ongoing impacts.

RESULTS

The majority of participants were women (n = 25), identified as Latina/o (n = 19), and rent their homes (n = 21). Participants described difficulty obtaining coherent information about the emergency, which resulted in feelings of abandonment. Most participants felt that local government and healthcare providers downplayed and/or disregarded their concerns despite ongoing odors and health symptoms. Participants described experiencing stress from the odors' unknown health effects and continued fear of future odor incidents. Residents sought to take control of the crisis through information sharing, community networking, and activism. Participants experienced longer term effects from this event, including increased awareness of pollution and reduced trust in local agencies.

DISCUSSION

This study demonstrates the necessity of clear, comprehensive, and prompt responses by relevant decisionmakers to chemical emergencies to appropriately address residents' fears, curb the spread of misinformation, and minimize adverse health effects. Participant responses also point to the benefit of supporting horizontal community networks for improved information sharing. By engaging directly with community members, researchers and disaster responders can better understand the various and complex impacts of chemical disasters and can improve response.

Central sleep apnea and exposure to ambient hydrogen sulfide emissions from massive strandings of decomposing sargassum in the Caribbean

BACKGROUND

Sargassum invasion of Caribbean and American shorelines is a recurring environmental hazard. Potential health effects of long-term chronic exposure to sargassum gaseous emissions, notably hydrogen sulfide (H2S), are overlooked. H2S plays an important role in neurotransmission and is involved in generating and transmitting respiratory rhythm. Central sleep apnea (CSA) has been attributed to the depression of respiratory centers.

OBJECTIVE

Evaluate the effects of exposure to sargassum-H2S on CSA.

METHODS

This study, set in the Caribbean, describes the clinical and polysomnographic characteristics of individuals living and/or working in areas impacted by sargassum strandings, in comparison with non-exposed subjects. Environmental exposure was estimated by the closest ground H2S sensor. Multivariate linear regression was applied to analyze CSA changes according to cumulative H2S exposure over time. Effects of air pollution and other sargassum toxic compounds (NH3) on CSA were also controlled.

RESULTS

Among the 685 study patients, 27 % were living and/or working in sargassum impacted areas. Compared with non-exposed patients, exposed ones had similar sleep apnea syndrome risk factors, but had increased levels of CSA events (expressed as absolute number or % of total sleep apnea). Multivariate regression retained only male gender and mean H2S concentration over a 6-month exposure period as independent predictors of an increase in CSA events. A minimal exposure length of 1 month generated a significant rise in CSA events, with the latter increasing proportionally with a cumulative increase in H2S concentration over time.

CONCLUSION

This pioneer work highlights a potential effect of sargassum-H2S on the central nervous system, notably on the modulation of the activity of the brain's respiratory control center. These observations, jointly with previous studies from our group, constitute a body of evidence strongly supporting a deleterious effect of sargassum-H2S on the health of individuals chronically exposed to low to moderate concentration levels over time.

Respiratory and nervous system effects of a hydrogen sulfide crisis in Carson, California

BACKGROUND

In October 2021, many residents in Carson, California experienced malodors, headaches, and respiratory symptoms. Hydrogen sulfide (H2S), a toxic odorous gas, was measured in Carson at concentrations up to 7000 parts per billion (ppb) and remained above California's acute air quality standard of 30 ppb for about a month. Research on how low- and medium-level H2S exposure affects the respiratory and nervous systems has yielded conflicting results, and few studies have examined the effects of subacute H2S exposure.

METHODS

We calculated daily rates of emergency department (ED) visits with various respiratory and nervous systems diagnosis codes in Carson area ZIP codes (≤6 km from event's epicenter) and in Los Angeles County ZIP codes >15 km from event's epicenter (control area). Using controlled interrupted time series, we compared ED visit rates during the month of the H2S crisis in Carson to the predicted rates had the incident not occurred, based on 2018-2021 ED trends, and controlling for ED visit rate changes in the control area.

RESULTS

We observed a 24 % increase in ED visit rate for all respiratory system diseases (rate ratio = 1.24, 95 % CI: 1.16, 1.32), a 38 % increase for asthma (RR = 1.38, 95 % CI: 1.26, 1.50), a 26 % increase for acute upper respiratory infections (RR = 1.26, 95 % CI: 1.13, 1.38), a 21 % increase for dizziness (RR = 1.21, 95 % CI: 1.04, 1.38), and a 25 % increase for migraines and headaches (RR = 1.25, 95 % CI: 1.13, 1.36) in the Carson area during the first month of the H2S event compared to the expected rates.

CONCLUSIONS

This H2S crisis was associated with increased ED visit rates for multiple respiratory and nervous system outcomes. Reducing H2S exposure and improving to response during H2S episodes may improve public health.

Residents' experiences during a hydrogen sulfide crisis in Carson, California

Background

In early October 2021, thousands of residents in Carson, California began complaining of malodors and headaches. The odor was identified as hydrogen sulfide (H2S), a noxious odorous gas. H2S was measured at concentrations up to 7000 parts per billion (ppb) and remained above California's acute air quality standard of 30 ppb for a month, with intermittent elevations continuing for 3 months. After 2 months of malodor in this environmental justice community, the H2S was attributed to a warehouse fire. Research has yielded conflicting results on the health effects of H2S exposure at levels that were experienced during this event. There remains a gap in understanding how people perceive and experience odor emergencies such as this H2S event.

Methods

Through a community-academic partnership, we conducted 6 focus groups in Carson with 33 participants who resided in the Carson area during the crisis. We sought to understand how this incident affected residents through facilitated discussion on topics including information acquisition, impressions of the emergency response, physical and mental health symptoms, and ongoing impacts.

Results

The majority of participants were women (n = 25), identified as Latina/o (n = 19), and rent their homes (n = 21). Participants described difficulty obtaining coherent information about the emergency, which resulted in feelings of abandonment. Most participants felt that local government and health care providers downplayed and/or disregarded their concerns despite ongoing odors and health symptoms. Participants described experiencing stress from the odors' unknown health effects and continued fear of future odor incidents. Residents sought to take control of the crisis through information sharing, community networking, and activism. Participants experienced longer term effects from this event, including increased awareness of pollution and reduced trust in local agencies.

Discussion

This study demonstrates the necessity of clear, comprehensive, and prompt responses by relevant decisionmakers to chemical emergencies to appropriately address residents' fears, curb the spread of misinformation, and minimize adverse health effects. Participant responses also point to the benefit of supporting horizontal community networks for improved information sharing. By engaging directly with community members, researchers and disaster responders can better understand the various and complex impacts of chemical disasters and can improve response.

Modeling and Analysis of Air Pollution and Environmental Justice: The Case for North Carolina's Hog Concentrated Animal Feeding Operations

BACKGROUND

Concentrated animal feeding operations (CAFOs) emit pollutants that can cause negative impacts on human health. The concentration of hog production in North Carolina raises concerns regarding the disproportionate exposure of vulnerable communities to air pollution from CAFOs.

OBJECTIVES

We investigated whether exposure to gaseous ammonia (NH 3 ) and hydrogen sulfide (H 2 S ) (in 2019) differs between subpopulations by examining demographics, including race/ethnicity, age, educational attainment, language proficiency, and socioeconomic status.

METHODS

We used an Air Monitoring Station (AMS)/Environmental Protection Agency (EPA) Regulatory Model (AERMOD)-based Human Exposure Model (version 3) to estimate ambient concentrations of NH 3 and H 2 S from hog farms in Duplin County and its surrounding counties in North Carolina and estimate subsequent exposures of communities within 50 km of Duplin County, North Carolina, or the Duplin County Region. We combined estimated exposures with 2016 American Community Summary Census data, at the block group level, using spatial analysis to investigate whether exposures to these pollutants differ by race and ethnicity, age, income, education, and language proficiency. Based on these estimations, we assessed associated exposure risks to the impacted communities and used multivariable regression modeling to evaluate the relationship between average ammonia exposures from Duplin regional hog farms and the presence of vulnerable populations.

RESULTS

The average [± standard deviation  ( SD ) ] annual estimated concentration of NH 3 and H 2 S in the Duplin County Region is 1.75 ± 2.81   μ g / m 3 and 0.0087 ± 0.014   μ g / m 3 , respectively. The maximum average annual ambient concentrations are estimated at 54.27 ± 4.12   μ g / m 3 and 0.54 ± 0.041   μ g / m 3 for NH 3 and H 2 S , respectively. Our descriptive analysis reveals that people of low income, people of color, people with low educational attainment, and the linguistically isolated in the Duplin Region are disproportionately exposed to higher levels of pollutants than the average exposure for residents. Alternatively, our statistical results suggests that after adjusting for covariates, communities of color are associated with 1.70% (95% CI: - 3.79 , 0.44) lower NH 3 concentrations per 1-SD increase. One-standard deviation increases in the adults with low educational attainment and children < 19 years of age is associated with 1.26% (95% CI: - 0.77 , 3.33) and 1.20% (95% CI: - 0.62 , 3.05) higher NH 3 exposure per 1-SD increase, respectively.

DISCUSSION

Exposures to NH 3 and H 2 S differed by race and ethnicity, educational attainment, language proficiency, and socioeconomic status. The observed associations between exposure to CAFO-generated pollutants and sociodemographic indicators differed among demographics. The disproportionate distribution of hog facilities and resulting pollutant exposures among communities may have adverse environmental and human health impacts, raising environmental justice concerns. https://doi.org/10.1289/EHP11344.

Low level exposure to hydrogen sulfide: a review of emissions, community exposure, health effects, and exposure guidelines

Hydrogen sulfide (H2S) is a toxic gas that is well-known for its acute health risks in occupational settings, but less is known about effects of chronic and low-level exposures. This critical review investigates toxicological and experimental studies, exposure sources, standards, and epidemiological studies pertaining to chronic exposure to H2S from both natural and anthropogenic sources. H2S releases, while poorly documented, appear to have increased in recent years from oil and gas and possibly other facilities. Chronic exposures below 10 ppm have long been associated with odor aversion, ocular, nasal, respiratory and neurological effects. However, exposure to much lower levels, below 0.03 ppm (30 ppb), has been associated with increased prevalence of neurological effects, and increments below 0.001 ppm (1 ppb) in H2S concentrations have been associated with ocular, nasal, and respiratory effects. Many of the studies in the epidemiological literature are limited by exposure measurement error, co-pollutant exposures and potential confounding, small sample size, and concerns of representativeness, and studies have yet to consider vulnerable populations. Long-term community-based studies are needed to confirm the low concentration findings and to refine exposure guidelines. Revised guidelines that incorporate both short- and long-term limits are needed to protect communities, especially sensitive populations living near H2S sources.

The association of unconventional natural gas development with diagnosis and treatment of internalizing disorders among adolescents in Pennsylvania using electronic health records

BACKGROUND

Unconventional natural gas development (UNGD) introduces physical and psychosocial hazards into communities, which could contribute to psychosocial stress in adolescents and an increased risk of internalizing disorders, common and impactful health outcomes.

OBJECTIVES

To evaluate associations between a 180-day composite UNGD activity metric and new onset of internalizing disorders, overall and separately for anxiety and depressive disorders, and effect modification by sex.

METHODS

We used a nested case-control design from 2008 to 2016 in 38 Pennsylvania counties using electronic health records from adolescent Geisinger subjects. Cases were defined by at least two diagnoses or medication orders indicating new onset of an internalizing disorder, and controls frequency-matched 4:1 on age, sex, and year. To evaluate associations, we used generalized estimating equations, with logit link, robust standard errors, and an exchangeable correlation structure within community.

RESULTS

We identified 7,974 adolescents (65.9% female, mean age 15.0 years) with new onset internalizing disorders. There were no associations when we used data from the entire study period. When restricted to years with higher UNGD activity (2010-2016), comparing the highest to lowest quartile, UNGD activity was associated (odds ratio [95% confidence level]) with new onset internalizing disorders (1.15 [1.06, 1.25]). Associations were slightly stronger for depressive disorders. Associations were only present in females (p = 0.009).

DISCUSSION

This is the first epidemiologic study of UNGD in relation to adolescent mental health, an important health outcome in a potentially susceptible group to the environmental and community impacts of UNGD. UNGD activity was associated with new onset internalizing disorders in females in this large sample in an area of active UNGD.

Measuring the Economic Value of the Negative Externality of Livestock Malodor in South Korea

The South Korean livestock industry has increased in scale and production, generating positive impacts on the national economy. However, livestock externalities, primarily malodor, have subsequently led to increased conflicts between producers and affected communities. This study estimated Korean households’ willingness-to-pay (WTP) for government subsidies to help address livestock malodor using a contingent valuation method (CVM) derived from a double-bounded dichotomous choice model. The annual average household WTP was estimated at 29,206 Korean won (KRW) (USD 25). This was slightly higher than the respondents’ self-reported average amount of KRW 25,457 (USD 22). The estimated economic value nationally is KRW 628 billion (USD 546 million) annually, for a total of KRW 3.14 trillion (USD 2.73 billion) over a proposed five-year period. The public’s estimated WTP can be leveraged to improve livestock management practices, more efficient waste disposal techniques, and improved husbandry methods to address conflicts between producers and surrounding communities.

Effects of ambient air pollution on psychological stress and anxiety disorder: a systematic review and meta-analysis of epidemiological evidence

OBJECTIVES

Ambient air pollution (AAP) is an important risk factor for increased mental health morbidity. Studies have highlighted the effect of AAP on psychological stress and anxiety disorder. However, existing evidence regarding this is largely equivocal. This systematic review with meta-analysis aims to synthesize published evidence to calculate the pooled estimate of the effect of AAP on psychological stress and anxiety disorder.

CONTENT

A systematic bibliographic search was undertaken using PubMed, JGateplus, Google Scholar, and Cochrane Library for observational human studies published in English till 31st March 2020 reporting the effect of AAP on psychological stress and anxiety disorder. Study quality was assessed using the Joanna Briggs Institute critical appraisal tools. Meta-analysis was performed adopting a random-effects model using Meta-XL. Of 412 articles retrieved, a total of 30 articles [AAP and anxiety disorders, (n=17, 57%); AAP and psychological stress, (n=9, 30%) and AAP and both psychological stress and anxiety disorders, (n=4, 13%)] fulfilled the inclusion criteria covering a total population of 973,725 individuals. The pooled estimate (OR) of the effects of PM₁₀ on psychological stress was 1.03 [(95% CI: 1.00, 1.05) (p=0.17, I ²=41%)]. The pooled estimate of the effects of NO₂ and PM₁₀ on anxiety disorder was 0.93 [(95% CI: 0.89, 0.97) (p=0.91, I ²=0%)] and 0.88 [(95% CI: 0.78, 0.98) (p=0.01, I ²=59%)] respectively. The pooled estimate of the effects of PM_2.5 on anxiety Disorder was 0.88 [(95% CI: 0.72, 1.06) (p=0.00, I ²=80%)].

SUMMARY AND OUTLOOK

The present study provides the most updated pooled estimate of the effect of AAP on psychological stress and anxiety disorder. Future studies should focus on longitudinal studies conducted in LIC and LMIC countries using uniform and standardized criteria for exposure and outcome assessment as well as robust adjustment for confounders to minimize methodological heterogeneity resulting in reliable and comparable estimation of environmental mental health burden.

Industrial odour pollution and human health: a systematic review and meta-analysis

OBJECTIVE

To conduct a systematic review to evaluate the association between residential or occupational short- and long-term exposure to odour pollution from industrial sources and the health status of the exposed population.

METHODS

The searches were conducted in Medline, EMBASE and Scopus in April 2021. Exposure to an environmental odour from industrial sources in population resident near the source or in workers was considered. We considered outcomes for which there was a biological plausibility, such as wheezing and asthma, cough, headache, nausea and vomiting (primary outcomes). We also included stress-related symptoms and novel outcomes (e.g. mood states). Risk of bias was evaluated using the OHAT tool. For primary outcomes, when at least 3 studies provided effect estimates by comparing exposed subjects versus not exposed, we pooled the study-specific estimates of odour-related effect using random effects models. Heterogeneity was evaluated with Higgins I2.

RESULTS

Thirty studies were eligible for this review, mainly cross-sectional (n = 23). Only one study involved school-age children and two studies involved workers. Only five studies reported odour effects on objective laboratory or clinical outcomes. Animal Feeding Operations and waste were the most common industrial sources. The overall odds ratios in exposed versus not exposed population were 1.15 (95% CI 1.01 to 1.29) for headache (7 studies), 1.09 (95% CI 0.88 to 1.30) for nausea/vomiting (7 studies), and 1.27 (95% CI 1.10 to 1.44) for cough/phlegm (5 studies). Heterogeneity was a moderate concern. Overall, the body of evidence was affected by a definitely high risk of bias in exposure and outcome assessment since most studies used self-reported information.

CONCLUSIONS

Findings underline the public health importance of odour pollution for population living nearby industrial odour sources. The limited evidence for most outcomes supports the need for high quality epidemiological studies on the association between odour pollution and its effects on human health.

Application of Olfactometry to Assess the Anti-Odor Properties of Filtering Facepiece Respirators Containing Activated Carbon Nonwovens

Filtering facepiece respirators (FFR) with anti-odor properties are used to reduce odor nuisance occurring both in everyday life and at workplaces. Unfortunately, there are no standardized methods to measure the efficiency of odor reduction of such personal protective devices. This paper aims to determine whether olfactometric-based methods, commonly used in environmental studies, can be employed for this purpose. The proposed procedure is based on the detection of n-butanol by study participants, and it consists of three subsequent stages: (i) defining the individual levels of odor sensitivity of each study participant; (ii) determining THE odor detection level while using FFRs with varying anti-odor properties; and (iii) completing a questionnaire concerning the subjective perceptions of study participants. As a measure of odor reduction efficiency, a coefficient W, defined as a quotient of the degree of odor reduction by the FFR, and the individual odor sensitivity of the subject, was proposed. The experimental results showed the ability of our measure to differentiate the effectiveness of odor reduction of tested FFRs. This indicates that it can be potentially employed as the assessment tool to confirm the effectiveness of such respiratory protective devices as a control measure mitigating the adverse effects of malodors on workers’ health, cognition, and behavior.

Relation of repeated exposures to air emissions from swine industrial livestock operations to sleep duration and awakenings in nearby residential communities

OBJECTIVES

Since waste from swine industrial livestock operations (ILOs) produces air pollutants associated with negative health outcomes among nearby residents, we assessed the impact of odorant emissions on sleep duration and awakenings.

DESIGN

A repeated-measures design.

SETTING

Sixteen residential communities in eastern North Carolina hosting swine ILOs.

PARTICIPANTS

Eighty participants residing in eastern North Carolina from 2003 to 2005.

INTERVENTION (IF ANY)

Not applicable.

MEASUREMENTS

Study participants completed twice-daily diaries in which they rated the strength of hog odors and indicated whether they were asleep or awake per hour for 2 weeks. Simultaneously, a monitoring trailer placed in a central location in each community measured the atmospheric concentration of hydrogen sulfide (H₂S). Subject-conditional fixed-effects regression models were used to estimate associations between 2 markers of swine ILO pollutant exposures (H₂S and swine odor) and 2 self-reported sleep outcomes (nightly sleep duration and awakening from sleep).

RESULTS

Among 80 participants, nightly (across a 12-hour period) swine odor was associated with lower nightly sleep duration (mean difference = -14.3 minutes, 95% confidence interval -25.0 to -3.3 minutes) compared to odor-free nights and detection of nightly hydrogen sulfide was associated with an increased risk of awakening (hazard ratio = 1.23, 95% confidence interval 0.98 to 1.55) compared to nights with no detection of hydrogen sulfide.

CONCLUSIONS

These results suggest that environmental odorants are important considerations for sleep health and highlight the importance of sleep as a potential mediator between environmental air pollution and health outcomes impacted by poor sleep.

Effects of trans-2-nonenal and olfactory masking odorants on proliferation of human keratinocytes

Malodorous compounds induce stress responses, mood changes, an increase of skin conductance, activation of the sympathetic nervous system and other physiological changes, and it has been suggested that sensing malodors could provide warning of danger to health. Furthermore, the human body secretes various malodorous compounds as waste products of metabolism, including trans-2-nonenal ((E)-2-nonenal), the amount of which increases with aging. In the present study, we examined the effects of some endogenous malodorous compounds ((E)-2-nonenal, nonanal, pentanal, hexanal, hexanoic acid, hexylamine and isovaleric acid) on cultured human keratinocytes. (E)-2-Nonenal decreased the viability and promoted apoptosis of cultured keratinocytes. It also reduced the thickness and the number of proliferative cells in a three-dimensional epidermal equivalent model. Co-application of masking odorants (dihydromycenol, benzaldehyde, linalool, phenethyl alcohol, benzyl acetate and anisaldehyde), but not non-masking odorants (1,8-cineol, β-damascone, and o-t-butylcyclohexyl acetate), reduced the effect of (E)-2-nonenal on keratinocyte proliferation, and restored the thickness and number of proliferative cells in a three-dimensional epidermal equivalent model.

COVID-19 Effects on Livestock Production: A One Welfare Issue

The COVID-19 pandemic highlights that we exist in a global community. From a single city, it spread to 188 countries across the world and infected 30 million people by September 18, 2020. Decades of modeling pandemics predicted potential consequences, but COVID-19's impact on the food supply chain, and specifically livestock production was unexpected. Clusters of cases among workers in meat processing plants evolved quickly to affect human, animal, and environmental welfare in several countries. In processing plants, the hygiene focus is on product quality and food safety. Because of their close proximity to one another, COVID-19 spread rapidly between workers and the lack of sick leave and health insurance likely resulted in workers continuing to work when infectious. In the United States (U.S.) many processing plants shut down when they identified major outbreaks, putting pressure especially on pig and poultry industries. At one point, there was a 45% reduction in pig processing capacity meaning about 250,000 pigs per day were not slaughtered. This resulted in longer transport distances to plants in operation with extra capacity, but also to crowding of animals on farm. Producers were encouraged to slow growth rates, but some had to cull animals on farm in ways that likely included suffering and caused considerable upset to owners and workers. Carcass disposal was also associated with potential biosecurity risks and detrimental effects on the environment. Hence, this is a One Welfare issue, affecting human, animal, and environmental welfare and highlighting the fragility of intensive, high-throughput livestock production systems. This model needs to be re-shaped to include the animal, human, and environmental elements across the farm to fork chain. Such a One Welfare approach will ensure that food production systems are resilient, flexible, and fair in the face of future challenges.

Product and cost perspectives of phosphorus recovery from human urine using solid waste ash and sea salt addition - A case of Thailand

Phosphorus (P) recovery from human urine was evaluated using the addition of MgCl₂, sea salt and solid-waste (SW) incinerated ashes. The study objectives were to assess and compare their efficiency for P recovery, costs of chemicals added and relevant crystal characteristics. Results from the experiments conducted between pH range of 7-11 revealed that P precipitation efficiency was increased to 89-97% and 72-88% when MgCl₂ and sea salt were added, respectively. Precipitates obtained from both cases were found to contain 10.8-17.1% P dry weight which is superior to commercial fertilizer (8.80% P). Based on SEM-EDS examination and chemical equilibrium thermodynamics, about 83% and 68% of precipitates were in the form of struvite for the addition of MgCl₂ and sea salt, respectively. Although 18% less struvite was formed with sea salt added, cost was found to be reduced from 4.07 USD·(kg P)^-1 for MgCl₂ addition to 2.91 USD·(kg P)^-1 using sea salt addition, representing a 28% cost reduction. Furthermore, SW ashes added into the urine increased P recovery efficiency about 6-17%. Addition also lowered the costs to 1.75 and 1.68 USD·(kg P)^-1 for SW fly ash and bottom ash, respectively. Thus, ash addition reduced cost and provided an alternative to landfill disposal. However, addition of SW bottom ash might result in recovered P solids with lead concentration exceeding the EC limit for inorganic fertilizer. In summary, results of this study have demonstrated a pragmatic way to recover P from human urine with the use of sea salt and ash as alternative Mg source and seed. Results indicate that this practice not only produces a good-quality fertilizer as struvite for sustainable P management, but also helps protect the water environment, and support circular economy of P in human ecosystem.

The Impact of Indoor Malodor: Historical Perspective, Modern Challenges, Negative Effects, and Approaches for Mitigation

Malodors, odors perceived to be unpleasant or offensive, may elicit negative symptoms via the olfactory system’s connections to cognitive and behavioral systems at levels below the known thresholds for direct adverse events. Publications on harm caused by indoor malodor are fragmented across disciplines and have not been comprehensively summarized to date. This review examines the potential negative effects of indoor malodor on human behavior, performance and health, including individual factors that may govern such responses and identifies gaps in existing research. Reported findings show that indoor malodor may have negative psychological, physical, social, and economic effects. However, further research is needed to understand whether the adverse effects are elicited via an individual’s experience or expectations or through a direct effect on human physiology and well-being. Conversely, mitigating indoor malodor has been reported to have benefits on performance and subjective responses in workers. Eliminating the source of malodor is often not achievable, particularly in low-income communities. Therefore, affordable approaches to mitigate indoor malodor such as air fresheners may hold promise. However, further investigations are needed into the effectiveness of such measures on improving health outcomes such as cognition, mood, and stress levels and their overall impact on indoor air quality.

Intensive Livestock Farming and Residential Health: Experts' Views

The presence of intensive livestock farms in close vicinity to residential areas in the Netherlands is a complex problem characterised by knowledge uncertainty about the effects on residential health, overlapping value-driven concerns and stakeholder diversity. In order to address concerns about the health effects and effectively manage the debate about intensive livestock farming, constructive stakeholder dialogues are encouraged, informed by current scientific insights. We explored the current knowledge, beliefs and concerns of scientific experts, following the mental models approach. A summary expert model was derived from scanning the relevant literature and informed by interviews with 20 scientific experts. The study shows imprecise use of terminology by experts. Moreover, they appear to perceive intensive livestock farming not as a major health problem at least at this moment for neighbouring residents in the Netherlands. Broader themes such as (environmental) unsustainability and biodiversity loss seem a more prominent concern among the experts. Our study questions whether dialogues should only focus on residential health or cover broader values and concerns. However, mental models about risk may differ with other stakeholders, impeding communication. Hence, we will identify other stakeholders' knowledge, beliefs and value-based concerns in the light of facilitating constructed dialogues between stakeholders.

Estimated time-varying exposures to air emissions from animal feeding operations and childhood asthma

BACKGROUND/AIM

Industrial-scale animal feeding operations (AFOs) have adverse impacts on regional air quality. Air emissions include endotoxins and other pro-inflammatory components, and exposure may cause airway inflammation and respiratory effects in susceptible individuals residing nearby. We aimed to develop and validate metrics for estimating time-varying exposure to AFO air pollution in surrounding communities and, secondly, to determine whether exposure is associated with health effects in children with asthma.

METHODS

We conducted a longitudinal panel study of N = 58 children with asthma in an agricultural region of Washington State with a high density of dairy AFOs. Children were followed for up to 26 months with repeated measures of respiratory health (N = 2023 interviews; N = 3853 lung function measurements); urine was collected in a subcohort (N = 16) at six-day intervals over three months and analyzed for leukotriene E4 (LTE4), a biomarker of systemic inflammation (N = 138 measurements). We developed an approach to estimate daily exposure to AFO airborne emissions based on distance to AFOs, AFO size, and daily wind speed and direction, and validated the estimates against direct measurements of ammonia, a chemical marker of AFO emissions, measured biweekly at 18 sites across the region for 14 months. Short-term relationships between AFO pollutant exposure and outcomes were assessed using regression models accounting for within-participant correlation and several potential confounders.

RESULTS

Estimates of daily AFO air pollution correlated moderately well with outdoor ammonia measurements (N = 842; r = 0.62). Forced expiratory volume in 1 s (FEV₁) as percent of predicted was 2.0% (95% CI: 0.5, 3.5) lower with each interquartile increase in previous day exposure, but no associations with asthma symptoms were observed. There was suggestive evidence that LTE4 concentrations were higher following days of elevated exposure to AFO emissions (p = 0.06).

CONCLUSIONS

A simple metric of time-varying exposure to AFO emissions was correlated with daily outdoor ammonia levels. Children with asthma may be adversely affected by exposure to AFO emissions.

Rapid Health Impact Assessment of a Proposed Poultry Processing Plant in Millsboro, Delaware

In 2013, Allen Harim Foods purchased the former site of a Vlasic Pickle plant in Millsboro, Delaware, and proposed to convert the site into a poultry processing plant that would process approximately two million birds weekly. This generated concerns about the proposed plant’s potential to impact health and quality of life among residents. We conducted a rapid health impact assessment (HIA) of the proposed plant to assess baseline environmental health issues in the host community and projected impacts. The scoping and baseline assessment revealed social, economic, and health disparities in the region. We also determined that residents in the area were already underserved and overburdened with pollution from multiple environmental hazards near the proposed plant including two sites contaminated with hazardous wastes, a power plant, and another poultry processing plant. The projected size and amount of poultry to be processed at the plant would likely cause increased levels of air, soil and water pollution, additional odor issues, and increased traffic and related pollution and safety issues. The information generated from the HIA formed the basis of a campaign to raise awareness about potential problems associated with the new facility and to foster more engagement of impacted residents in local decision-making about the proposed plant. In the end, the HIA helped concerned residents oppose the new poultry processing plant. This case study provides an example of how HIAs can be used as a tool to educate residents, raise awareness about environmental justice issues, and enhance meaningful engagement in local environmental decision-making processes.

Subjective unpleasantness of malodors induces a stress response

Unpleasant odors impair our mood and may affect physical health, even when the odorants are not toxic. A possible cause for such negative effects is stress induced by odors; however, whether the unpleasantness itself elicited stress or not has not been clear. Thus, we examined whether unpleasantness of odors induced the stress responses of emotion, the hypothalamic-pituitary-adrenal (HPA) axis, and the sympathetic nervous system (SNS). Six experiments were conducted, where salivary cortisol or salivary alpha amylase (sAA), markers for activities of the HPA and the SNS, respectively, were measured, along with subjective ratings of odors and emotion. First, the responses to three malodors listed in the Offensive Odor Control Law in Japan were examined. While these odors were rated as unpleasant, and exposure to them increased anxiety, no response of the HPA was observed (experiment 1, n = 69). In contrast, an increase of the SNS activity was observed after exposure to two of the three malodors, while the SNS did not respond to pleasant odors (experiments 2-4, n = 35, 34 and 30). To examine the effect of unpleasantness further, the SNS response was examined while subjective unpleasantness of odors was manipulated by adding negative verbal information (experiment 5, n = 92), or by mixing in a pleasant odor (experiment 6, n = 35). The SNS responses upon inhalation of the same odorous substances were found to be dependent on whether they were perceived as unpleasant. Finally, a correlation analysis on the pooled data from experiments 2-6 showed that the odor-elicited SNS activity and anxiety were strongly correlated with perceived unpleasantness of odors. These results suggest that subjective unpleasantness of odors per se can induce the stress response of emotion and the SNS.

Air pollution, stock returns, and trading activities in China☆

The relationship between air pollution and stock pricing of locally headquartered firms is explored using firm-level data in China. Severe air pollution results in low returns, turnover, volatility, and high illiquidity, mainly through a home bias. The results remain robust after a series of checks. The relation between air pollution and local firm performance is insignificant, implying that the air pollution effects can be attributed to investor mood bias rather than to economic effects. The sensitivity of stock returns to air pollution is significantly large for high-growth stocks, distressed stocks, and stocks with high volatility.

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We examine how air pollution affects stock pricing of locally headquartered firms.

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We validate that air pollution is one of factors inducing pessimistic moods.

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Severe air pollution decreases local stock returns, liquidity and volatility.

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Air pollution effect is more pronounced for stocks hard to value and arbitrage.

Spatiotemporal Industrial Activity Model for Estimating the Intensity of Oil and Gas Operations in Colorado

Oil and gas (O&G) production in the United States has increased in the last 15 years, and operations, which are trending toward large multiwell pads, release hazardous air pollutants. Health studies have relied on proximity to O&G wells as an exposure metric, typically using an inverse distance-weighting (IDW) approach. Because O&G emissions are dependent on multiple factors, a dynamic model is needed to describe the variability in air pollution emissions over space and time. We used information on Colorado O&G activities, production volumes, and air pollutant emission rates from two Colorado basins to create a spatiotemporal industrial activity model to develop an intensity-adjusted IDW well-count metric. The Spearman correlation coefficient between this metric and measured pollutant concentrations was 0.74. We applied our model to households in Greeley, Colorado, which is in the middle of the densely developed Denver-Julesburg basin. Our intensity-adjusted IDW increased the unadjusted IDW dynamic range by a factor of 19 and distinguishes high-intensity events, such as hydraulic fracturing and flowback, from lower-intensity events, such as production at single-well pads. As the frequency of multiwell pads increases, it will become increasingly important to characterize the range of intensities at O&G sites when conducting epidemiological studies.

O'Connor et al. systematic review regarding animal feeding operations and public health: critical flaws may compromise conclusions

In this comment, we summarize several scientific concerns with the recently published systematic review from O'Connor and colleagues that examined the relationship between proximity to animal-feeding operations and health of individuals in nearby communities. The authors utilized a bias tool not designed for environmental health research, erroneously excluded important studies, and incorrectly interpreted others. As a result, the conclusions drawn in the review misrepresent the evidence from the published literature, limiting its value to policymakers, researchers, and the public.

Reviewing putative industrial triggering in pemphigus: cluster of pemphigus in the area near the wastewater treatment plant

A range of pemphigus is relatively rare potentially fatal group of autoimmune blistering dermatoses. Usually, there is no apparent triggering, while in some predisposed patients there are alleged environmental/industrial inducing factors. In a short time period (4 years), we diagnosed 3 novel cases of pemphigus (1 pemphigus vulgaris, 1 pemphigus foliaceus and 1 shift from pemphigus foliaceus into pemphigus vulgaris) at a clinical and laboratory level (ELISA, immunofluorescence studies). We discuss a possible common inducing mechanism as these patients inhabit one estate of the Poznan suburbia (Kozieglowy, population < 12,000), Greater Poland district, Poland, and review literature data on alleged pemphigus triggers. To the best of our knowledge, this is the first report exploring the putative association between pemphigus diseases and wastewater treatment plant waterborne or volatile by-products in the vicinity of such a facility.

Updated systematic review: associations between proximity to animal feeding operations and health of individuals in nearby communities

OBJECTIVE

The objective of this review was to update a systematic review of associations between living near an animal feeding operation (AFO) and human health.

METHODS

The MEDLINE® and MEDLINE® In-Process, Centre for Agricultural Biosciences Abstracts, and Science Citation Index databases were searched. Reference lists of included articles were hand-searched. Eligible studies reported exposure to an AFO and an individual-level human health outcome. Two reviewers performed study selection and data extraction.

RESULTS

The search returned 3702 citations. Sixteen articles consisting of 10 study populations were included in the analysis. The health outcomes were lower and upper respiratory tracts, MRSA, other infectious disease, neurological, psychological, dermatological, otologic, ocular, gastrointestinal, stress and mood, and other non-infectious health outcomes. Most studies were observational and used prevalence measures of outcome. An association between Q fever risk and proximity to goat production was reported. Other associations were unclear. Risk of bias was serious or critical for most exposure-outcome associations. Multiplicity (i.e., a large number of potentially correlated outcomes and exposures assessed on the same study subjects) was common in the evidence base.

CONCLUSIONS

Few studies reported an association between surrogate clinical outcomes and AFO proximity for respiratory tract-related outcomes. There were no consistent dose-response relationships between surrogate clinical outcome and AFO proximity. A new finding was that Q fever in goats is likely associated with an increased Q fever risk in community members. The review results for the non-respiratory health outcomes were inconclusive because only a small number of studies were available or the between-study results were inconsistent.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42014010521.

An Overview of Literature Topics Related to Current Concepts, Methods, Tools, and Applications for Cumulative Risk Assessment (2007-2016)

Cumulative risk assessments (CRAs) address combined risks from exposures to multiple chemical and nonchemical stressors and may focus on vulnerable communities or populations. Significant contributions have been made to the development of concepts, methods, and applications for CRA over the past decade. Work in both human health and ecological cumulative risk has advanced in two different contexts. The first context is the effects of chemical mixtures that share common modes of action, or that cause common adverse outcomes. In this context two primary models are used for predicting mixture effects, dose addition or response addition. The second context is evaluating the combined effects of chemical and nonchemical (e.g., radiation, biological, nutritional, economic, psychological, habitat alteration, land-use change, global climate change, and natural disasters) stressors. CRA can be adapted to address risk in many contexts, and this adaptability is reflected in the range in disciplinary perspectives in the published literature. This article presents the results of a literature search and discusses a range of selected work with the intention to give a broad overview of relevant topics and provide a starting point for researchers interested in CRA applications.

Health conditions in rural areas with high livestock density: Analysis of seven consecutive years

Previous studies investigating health conditions of individuals living near livestock farms generally assessed short time windows. We aimed to take time-specific differences into account and to compare the prevalence of various health conditions over seven consecutive years. The sample consisted of 156,690 individuals registered in 33 general practices in a (rural) area with a high livestock density and 101,015 patients from 23 practices in other (control) areas in the Netherlands. Prevalence of health conditions were assessed using 2007-2013 electronic health record (EHR) data. Two methods were employed to assess exposure: 1) Comparisons between the study and control areas in relation to health problems, 2) Use of individual estimates of livestock exposure (in the study area) based on Geographic Information System (GIS) data. A higher prevalence of chronic bronchitis/bronchiectasis, lower respiratory tract infections and vertiginous syndrome and lower prevalence of respiratory symptoms and emphysema/COPD was found in the study area compared with the control area. A shorter distance to the nearest farm was associated with a lower prevalence of upper respiratory tract infections, respiratory symptoms, asthma, COPD/emphysema, allergic rhinitis, depression, eczema, vertiginous syndrome, dizziness and gastrointestinal infections. Especially exposure to cattle was associated with less health conditions. Living within 500m of mink farms was associated with increased chronic enteritis/ulcerative colitis. Livestock-related exposures did not seem to be an environmental risk factor for the occurrence of health conditions. Nevertheless, lower respiratory tract infections, chronic bronchitis and vertiginous syndrome were more common in the area with a high livestock density. The association between exposure to minks and chronic enteritis/ulcerative colitis remains to be elucidated.

Hydrogen sulfide concentrations at three middle schools near industrial livestock facilities

Safe school environments are essential for healthy development, yet some schools are near large-scale livestock facilities that emit air pollution. Hydrogen sulfide (H₂S) from decomposing manure is an indicator of livestock-related air pollution. We measured outdoor concentrations of H₂S at three public middle schools near livestock facilities in North Carolina. We used circular graphs to relate H₂S detection and wind direction to geospatial distributions of nearby livestock barns. We also used logistic and linear regression to model H₂S in relation to upwind, distance-weighted livestock barn area. Circular graphs suggested an association between upwind livestock barns and H₂S detection. The log-odds of H₂S detection per 1000 m² increased with upwind weighted swine barn area (School A: β-coefficient (β)=0.43, SE=0.06; School B: β=0.64, SE=0.24) and upwind weighted poultry barn area (School A: β=0.05, SE=0.01), with stronger associations during periods of atmospheric stability than atmospheric instability (School A stable: β=0.69, SE=0.11; School A unstable: β=0.32, SE=0.09). H₂S concentration also increased linearly with upwind swine barn area, with greater increases during stable atmospheric conditions (stable: β=0.16 parts per billion (p.p.b.), SE=0.01; unstable: β=0.05 p.p.b., SE=0.01). Off-site migration of pollutants from industrial livestock operations can decrease air quality at nearby schools.

Pragmatic evaluation of odour emissions from a rendering plant in southern Brazil

In the food industry and linked activities, environmental impacts relate mainly to the generation of liquid and gaseous effluents. Rendering plants, which process animal by-products, are strongly associated with malodorous emissions. Thus, effective odour-control technologies are required to minimise odour annoyance in nearby communities and thereby public complaints. In this paper, the effectiveness of a biofilter for the treatment of odours from a meat-rendering plant located in southern Brazil was evaluated based on German guideline VDI 3477:2004-11. Samples were collected upstream and downstream of the gas treatment system using a pragmatic approach in order to minimise the cost of such a study. Odour concentration was determined according to European standard EN 13725:2003. The results showed an OER of 8.82 × 10⁸ ou_E h^-1 and odour removal efficiency lower than the established benchmark set by SEMA Resolution 054/2006, taken as reference for being the only Brazilian regulation to establish quantitative odour emission criteria. Enhancement of the biofiltration system and/or association with other odour abatement technologies are required to increase odour removal, limit impacts and comply with regulatory requirements. The paper also includes a discussion on the current odour regulation in Brazil.

Characterization of exposure in epidemiological studies on air pollution from biodegradable wastes: Misclassification and comparison of exposure assessment strategies

The assignment of exposure is one of the main challenges faced by environmental epidemiologists. However, misclassification of exposures has not been explored in population epidemiological studies on air pollution from biodegradable wastes. The objective of this study was to investigate the use of different approaches for assessing exposure to air pollution from biodegradable wastes by analyzing (1) the misclassification of exposure that is committed by using these surrogates, (2) the existence of differential misclassification (3) the effects that misclassification may have on health effect estimates and the interpretation of epidemiological results, and (4) the ability of the exposure measures to predict health outcomes using 10-fold cross validation. Four different exposure assessment approaches were studied: ammonia concentrations at the residence (Metric I), distance to the closest source (Metric II), number of sources within certain distances from the residence (Metric IIIa,b) and location in a specific region (Metric IV). Exposure-response models based on Metric I provided the highest predictive ability (72.3%) and goodness-of-fit, followed by IV, III and II. When compared to Metric I, Metric IV yielded the best results for exposure misclassification analysis and interpretation of health effect estimates, followed by Metric IIIb, IIIa and II. The study showed that modelled NH₃ concentrations provide more accurate estimations of true exposure than distances-based surrogates, and that distance-based surrogates (especially those based on distance to the closest point source) are imprecise methods to identify exposed populations, although they may be useful for initial studies.

Industrial Food Animal Production and Community Health

Industrial food animal production (IFAP) is a source of environmental microbial and chemical hazards. A growing body of literature suggests that populations living near these operations and manure-applied crop fields are at elevated risk for several health outcomes. We reviewed the literature published since 2000 and identified four health outcomes consistently and positively associated with living near IFAP: respiratory outcomes, methicillin-resistant Staphylococcus aureus (MRSA), Q fever, and stress/mood. We found moderate evidence of an association of IFAP with quality of life and limited evidence of an association with cognitive impairment, Clostridium difficile, Enterococcus, birth outcomes, and hypertension. Distance-based exposure metrics were used by 17/33 studies reviewed. Future work should investigate exposure through drinking water and must improve exposure assessment with direct environmental sampling, modeling, and high-resolution DNA typing methods. Investigators should not limit study to high-profile pathogens like MRSA but include a broader range of pathogens, as well as other disease outcomes.

Identifying Perceived Neighborhood Stressors Across Diverse Communities in New York City

There is growing interest in the role of psychosocial stress in health disparities. Identifying which social stressors are most important to community residents is critical for accurately incorporating stressor exposures into health research. Using a community-academic partnered approach, we designed a multi-community study across the five boroughs of New York City to characterize resident perceptions of key neighborhood stressors. We conducted 14 community focus groups; two to three in each borough, with one adolescent group and one Spanish-speaking group per borough. We then used systematic content analysis and participant ranking data to describe prominent neighborhood stressors and identify dominant themes. Three inter-related themes regarding the social and structural sources of stressful experiences were most commonly identified across neighborhoods: (1) physical disorder and perceived neglect, (2) harassment by police and perceived safety and (3) gentrification and racial discrimination. Our findings suggest that multiple sources of distress, including social, political, physical and economic factors, should be considered when investigating health effects of community stressor exposures and psychological distress. Community expertise is essential for comprehensively characterizing the range of neighborhood stressors that may be implicated in psychosocial exposure pathways.

Challenges and benefits of conducting environmental justice research in a school setting

Environmental justice (EJ) research requires attention to consequences for research participants beyond those typically considered by institutional review boards. The imbalance of power between impacted communities and those who create and regulate pollution creates challenges for participation, yet research can also benefit those involved. Our community-academic partnership designed the Rural Air Pollutants and Children's Health (RAPCH) study to provide positive impacts while measuring health effects at three low-resource public middle schools near concentrated animal feeding operations (CAFOs) in North Carolina. We evaluated perceived benefits and challenges of study involvement by interviewing school staff and community liaisons who facilitated data collection. Reported benefits included enhancement of students' academic environment and increased community environmental awareness; challenges were associated mainly with some participants' immaturity. Leadership from a strong community-based organization was crucial to recruitment, yet our approach entailed minimal focus on EJ, which may have limited opportunities for community education or organizing for environmental health.

Tale of two isomers: complexities of human odor perception for cis- and trans-4-methylcyclohexane methanol from the chemical spill in West Virginia

Application of gas chromatography with mass spectrometric and human olfactory "sniffer" detectors reveals the nature of odorous chemicals from an industrial chemical spill. Crude 4-methylcyclohexane methanol (4-MCHM) spilled in a river and then contaminated drinking water and air for over 300000 consumers living in West Virginia. Olfactory gas chromatography allows investigators to independently measure the odor of chemical components in a mixture. Crude 4-MCHM is comprised of several major cyclohexane components, four of which have distinct isomer pairs. The cis- and trans-4-MCHM isomers are the only components to have distinct odors at the concentrations used in this study. The trans-4-MCHM is the dominant odorant with descriptors of "licorice" and "sweet". Trans-4-MCHM has an air odor threshold concentration of 0.060 ppb-v (95% CI: 0.040-0.091). The odor threshold concentrations are not influenced by gender or age but are lower by a factor of 5 for individuals with prior exposure compared to naïve subjects. Individual trans-4-MCHM odor threshold concentrations vary by more than a factor of 100. The cis-4-MCHM isomer has approximately a 2000-fold higher odor threshold concentration, different descriptors, and an even wider individual response range.

Odors from sewage sludge and livestock: associations with self-reported health

OBJECTIVES

Class B treated sewage sludge (TSS) contains microbes and toxicants and is applied to land in areas where livestock wastes may be present. We evaluated relationships of reports of TSS and livestock odors with acute symptoms and excessive flies.

METHODS

A total of 158 adults living near liquid TSS application sites, 85 living near cake TSS application sites, and 188 living in comparison areas responded to a household survey regarding odors, health, and demographics. We identified symptom groups using factor analysis. We used generalized estimating equations to fit linear models for associations between factor scores and odors, and Poisson models for associations with specific symptoms.

RESULTS

Most factor scores were similar between exposure groups. Covariate-adjusted z-scores for lower respiratory symptoms were 0.28 (95% confidence interval [CI] -0.10, 0.65) higher among residents who reported moderate to very strong liquid TSS odor than among residents in comparison areas, and 0.28 (95% CI 0.05, 0.50) higher among residents who reported moderate to very strong livestock odor compared with residents reporting no or faint livestock odor. The factor score for dermatologic conditions was higher among residents who reported higher liquid sludge odor (0.27, 95% CI -0.13, 0.68), primarily due to skin rash (prevalence ratio = 2.21, 95% CI 1.13, 4.32). Excessive flies were reported twice as commonly among respondents who reported moderate to very strong TSS odor than among other residents.

CONCLUSIONS

Reported odors from TSS and livestock were associated with some acute symptoms. Health departments should monitor land applications of human and animal wastes and conduct surveillance of health problems reported by neighbors.

Chronic exposure to odorous chemicals in residential areas and effects on human psychosocial health: dose-response relationships

Perceived air pollution, including environmental odor pollution, is known to be an environmental stressor that affects individuals' psychosocial health and well-being. However, very few studies have been able to quantify exposure-response associations based on individual-specific residential exposures to a proxy gas and to examine the mechanisms underlying these associations. In this study, individual-specific exposures in non-urban residential environments during 2005-2010 on a gas released from animal biodegradable wastes (ammonia, NH3) were calculated by the Danish Eulerian long-range transport model and the local-scale transport deposition model. We used binomial and multinomial logistic regression and mediation analyses to examine the associations between average exposures and questionnaire-based data on psychosocial responses, after controlling for person-specific covariates. About 45% of the respondents were annoyed by residential odor pollution. Exposures were associated with annoyance (adjusted odds ratio [ORadj]=3.54, 95% confidence interval [CI]=2.33-5.39), health risk perception (ORadj=4.94; 95% CI=1.95-12.5) and behavioral interference (ORadj=3.28; 95% CI=1.77-6.11), for each unit increase in loge(NH3 exposure). Annoyance was a strong mediator in exposure-behavior interference and exposure-health risk perception relationships (81% and 44% mediation, respectively). Health risk perception did not play a mediating role in exposure-annoyance or exposure-behavioral interference relationships. This is the first study to provide a quantitative estimation of the dose-response associations between ambient NH3 exposures and psychosocial effects caused by odor pollution in non-urban residential outdoor environments. It further shows that these effects are both direct and mediated by other psychosocial responses. The results support the use of NH3 as a proxy gas of air pollution from animal biodegradable wastes in epidemiologic studies.

Investigating the role of state permitting and agriculture agencies in addressing public health concerns related to industrial food animal production

Objectives

Industrial food animal production (IFAP) operations adversely impact environmental public health through air, water, and soil contamination. We sought to determine how state permitting and agriculture agencies respond to these public health concerns.

Methods

We conducted semi-structured qualitative interviews with staff at 12 state agencies in seven states, which were chosen based on high numbers or rapid increase of IFAP operations. The interviews served to gather information regarding agency involvement in regulating IFAP operations, the frequency and type of contacts received about public health concerns, how the agency responds to such contacts, and barriers to additional involvement.

Results

Permitting and agriculture agencies’ responses to health-based IFAP concerns are constrained by significant barriers including narrow regulations, a lack of public health expertise within the agencies, and limited resources.

Conclusions

State agencies with jurisdiction over IFAP operations are unable to adequately address relevant public health concerns due to multiple factors. Combining these results with previously published findings on barriers facing local and state health departments in the same states reveals significant gaps between these agencies regarding public health and IFAP. There is a clear need for regulations to protect public health and for public health professionals to provide complementary expertise to agencies responsible for regulating IFAP operations.

Chronic ambient hydrogen sulfide exposure and cognitive function

BACKGROUND

Exposures to hydrogen sulfide gas (H2S) have been inconclusively linked to a variety of negative cognitive outcomes. We investigated possible effects on cognitive function in an urban population with chronic, low-level exposure to H2S.

METHODS

Participants were 1637 adults, aged 18-65 years from Rotorua city, New Zealand, exposed to ambient H2S from geothermal sources. Exposures at homes and workplaces were estimated from data collected by summer and winter H2S monitoring networks across Rotorua in 2010/11. Metrics for H2S exposure at the time of participation and for exposure over the last 30 years were calculated. H2S exposure was modeled both as continuous variables and as quartiles of exposure covering the range of 0-64 ppb (0-88 μg/m(3)). Outcomes were neuropsychological tests measuring visual and verbal episodic memory, attention, fine motor skills, psychomotor speed and mood. Associations between cognition and measures of H2S exposure were investigated with multiple regression, while covarying demographics and factors known to be associated with cognitive performance.

RESULTS

The consistent finding was of no association between H2S exposure and cognition. Quartiles of H2S exposure had a small association with simple reaction time: higher exposures were associated with faster response times. Similarly, for digit symbol, higher H2S exposures tended to be marginally associated with better performance.

CONCLUSION

The results provide evidence that chronic H2S exposure, at the ambient levels found in and around Rotorua, is not associated with impairment of cognitive function.

[Study of self-reported health of people living near point sources of environmental pollution: a review. Second part: analysis of results and perspectives]

BACKGROUND

Epidemiological studies have investigated the health impacts of local sources of environmental pollution using as an outcome variable self-reported health, reflecting the overall perception interviewed people have of their own health. This work aims at analyzing the advantages and the results of this approach. This second part presents the results of the studies.

METHODS

Based on a literature review (51 papers), this article presents an analysis of the contribution of self-reported health to epidemiological studies investigating local sources of environmental pollution. It discusses the associations between self-reported health and exposure variables, and other risk factors that can influence health reporting.

RESULTS

Studies using self-reported health showed that local sources can be associated with a wide range of health outcomes, including an impact on mental health and well-being. The perception of pollution, especially sensory information such as odors, affects self-reported health. Attitudes referring to beliefs, worries and personal behaviors concerning the source of pollution have a striking influence on reported health. Attitudes can be used to estimate the reporting bias in a biomedical approach, and also constitute the main explanatory factors in biopsychosocial studies taking into account not only the biological, physical, and chemical factors but also the psychological and social factors at stake in a situation of environmental exposure.

CONCLUSION

Studying self-reported health enables a multifactorial approach to health in a context of environmental exposure. This approach is most relevant when conducted within a multidisciplinary framework involving human and social sciences to better understand psychosocial factors. The relevance of this type of approach used as an epidemiological surveillance tool to monitor local situations should be assessed with regard to needs for public health management of these situations.