The relationship between fine particulate matter (PM2.5) and schizophrenia severity

Outdoor Air Pollution Relates to Amygdala Subregion Volume and Apportionment in Early Adolescents

Background

Outdoor air pollution is associated with an increased risk for psychopathology. Although the neural mechanisms remain unclear, air pollutants may impact mental health by altering limbic brain regions, such as the amygdala. Here, we examine the association between ambient air pollution exposure and amygdala subregion volumes in 9-10-year-olds.

Methods

Cross-sectional Adolescent Brain Cognitive DevelopmentSM (ABCD) Study® data from 4,473 participants (55.4% male) were leveraged. Air pollution was estimated for each participant's primary residential address. Using the probabilistic CIT168 atlas, we quantified total amygdala and 9 distinct subregion volumes from T1- and T2-weighted images. First, we examined how criteria pollutants (i.e., fine particulate matter [PM2.5], nitrogen dioxide, ground-level ozone) and 15 PM2.5 components related with total amygdala volumes using linear mixed-effect (LME) regression. Next, partial least squares correlation (PLSC) analyses were implemented to identify relationships between co-exposure to criteria pollutants as well as PM2.5 components and amygdala subregion volumes. We also conducted complementary analyses to assess subregion apportionment using amygdala relative volume fractions (RVFs).

Results

No significant associations were detected between pollutants and total amygdala volumes. Using PLSC, one latent dimension (LD) (52% variance explained) captured a positive association between calcium and several basolateral subregions. LDs were also identified for amygdala RVFs (ranging from 30% to 82% variance explained), with PM2.5 and component co-exposure associated with increases in lateral, but decreases in medial and central, RVFs.

Conclusions

Fine particulate and its components are linked with distinct amygdala differences, potentially playing a role in risk for adolescent mental health problems.

Association between indoor PM2.5 components and accelerated biological aging in schizophrenia patients: Evidence from multi-omics mechanisms

Indoor fine particulate matter (PM2.5) poses a considerable hazard to the aging process, particularly in vulnerable populations such as schizophrenia patients who frequently spend extended periods in indoor environments. Currently, the evidence on which PM2.5 components contribute to accelerated aging remains unclear. To address these issues, we conducted a prospective, repeated-measurement study on 104 schizophrenia patients. Our findings indicated that exposure to PM2.5 components was significantly associated with accelerated biological aging in schizophrenia patients. Notably, the most prominent effects were observed for thallium (1.303, 95 % CI: 0.481-2.125), chromium (1.029, 95 % CI: 0.303-1.756), lead (1.021, 95 % CI: 0.296-1.746), antimony (0.915, 95 % CI: 0.233-1.597), selenium (0.854, 95 % CI: 0.209-1.499), and manganese (0.833, 95 % CI: 0.186-1.480). Multivariate analysis revealed that PM2.5 components predominantly induced alterations in serum glycerophospholipid metabolites, accelerating the aging process. This intricate connection was closely linked to the gut microbiota, particularly to species such as Dorea and Blautia. Mediation analysis showed that the Blautia-PC (16:0/0:0) pathway mediated the largest proportion (30.69 %) of the effect of manganese exposure on accelerating immune biological aging in schizophrenia patients, as measured using the Klemera-Doubal method. These results underscore the need to address pollution sources that harm health, and provide new evidence for improving regional air quality.

Environmental pollution and extreme weather conditions: insights into the effect on mental health

Environmental pollution exposures, including air, soil, water, light, and noise pollution, are critical issues that may implicate adverse mental health outcomes. Extreme weather conditions, such as hurricanes, floods, wildfires, and droughts, may also cause long-term severe concerns. However, the knowledge about possible psychiatric disorders associated with these exposures is currently not well disseminated. In this review, we aim to summarize the current knowledge on the impact of environmental pollution and extreme weather conditions on mental health, focusing on anxiety spectrum disorders, autism spectrum disorders, schizophrenia, and depression. In air pollution studies, increased concentrations of PM2.5, NO2, and SO2 were the most strongly associated with the exacerbation of anxiety, schizophrenia, and depression symptoms. We provide an overview of the suggested underlying pathomechanisms involved. We highlight that the pathogenesis of environmental pollution-related diseases is multifactorial, including increased oxidative stress, systematic inflammation, disruption of the blood-brain barrier, and epigenetic dysregulation. Light pollution and noise pollution were correlated with an increased risk of neurodegenerative disorders, particularly Alzheimer's disease. Moreover, the impact of soil and water pollution is discussed. Such compounds as crude oil, heavy metals, natural gas, agro-chemicals (pesticides, herbicides, and fertilizers), polycyclic or polynuclear aromatic hydrocarbons (PAH), solvents, lead (Pb), and asbestos were associated with detrimental impact on mental health. Extreme weather conditions were linked to depression and anxiety spectrum disorders, namely PTSD. Several policy recommendations and awareness campaigns should be implemented, advocating for the advancement of high-quality urbanization, the mitigation of environmental pollution, and, consequently, the enhancement of residents' mental health.

Heatwave characteristics complicate the association between PM2.5 components and schizophrenia hospitalizations in a changing climate: Leveraging of the individual residential environment

BACKGROUND

In the era characterized by global environmental and climatic changes, understanding the effects of PM2.5 components and heatwaves on schizophrenia (SCZ) is essential for implementing environmental interventions at the population level. However, research in this area remains limited, which highlights the need for further research and effort. We aim to assess the association between exposure to PM2.5 components and hospitalizations for SCZ under different heatwave characteristics.

METHODS

We conducted a 16 municipalities-wide, individual exposure-based, time-stratified, case-crossover study from January 1, 2017, to December 31, 2020, encompassing 160736 hospitalizations in Anhui Province, China. Daily concentrations of PM2.5 components were obtained from the Tracking Air Pollution in China dataset. Conditional logistic regression models were used to investigate the association between PM2.5 components and hospitalizations. Additionally, restricted cubic spline models were used to identify protective thresholds of residential environment in response to environmental and climate change.

RESULTS

Our findings indicate a positive correlation between PM2.5 and its components and hospitalizations. Significantly, a 1 μg/m3 increase in black carbon (BC) was associated with the highest risk, at 1.58% (95%CI: 0.95-2.25). Exposure to heatwaves synergistically enhanced the impact of PM2.5 components on hospitalization risks, and the interaction varied with the intensity and duration of heatwaves. Under the 99th percentile heatwave events, the impact of PM2.5 and its components on hospitalizations was most pronounced, which were PM2.5 (2-4d: 4.59%, 5.09%, and 5.09%), sulfate (2-4d: 21.73%, 23.23%, and 25.25%), nitrate (2-4d: 17.51%, 16.93%, and 20.31%), ammonium (2-4d: 27.49%, 31.03%, and 32.41%), organic matter (2-4d: 32.07%, 25.42%, and 24.48%), and BC (2-4d: 259.36%, 288.21%, and 152.52%), respectively. Encouragingly, a protective effect was observed when green and blue spaces comprised more than 17.6% of the residential environment.

DISCUSSION

PM2.5 components and heatwave exposure were positively associated with an increased risk of hospitalizations, although green and blue spaces provided a mitigating effect.

Ecological correlation between short term exposure to particulate matter and hospitalization for mental disorders in Shijiazhuang, China

The associations between particulate matter (PM) and overall and specific mental disorders (MDs) are investigated using data from two general hospitals in Shijiazhuang, China, from January 2014 to December 2019. A longitudinal time series study, as one type of ecological study, is conducted using a generalized additive model to examine the relationship between short-term exposure to PM2.5, PM10, and daily hospital admissions for MDs, and further stratification by subtypes, age, and gender. A total of 10,709 cases of hospital admissions for MDs have been identified. The significant short-time effects of PM2.5 on overall MDs at lag01 and PM10 at lag05 are observed, respectively. For specific mental disorders, there are substantial associations of PM pollution with mood disorders and organic mental disorders. PM2.5 has the greatest cumulative effect on daily admissions of mood disorders and organic mental disorders in lag01, and PM 10 has the greatest cumulative effect in lag05. Moreover, the effect modification by sex or age is statistically significant, with males and the elderly (≥ 45 years) having a stronger effect. Short-term exposure to PM2.5 and PM10can be associated with an increased risk of daily hospital admissions for MDs.

Critical review on emerging health effects associated with the indoor air quality and its sustainable management

Indoor air quality (IAQ) is one of the fundamental elements affecting people's health and well-being. Currently, there is a lack of awareness among people about the quantification, identification, and possible health effects of IAQ. Airborne pollutants such as volatile organic compounds (VOCs), particulate matter (PM), sulfur dioxide (SO2), carbon monoxide (CO), nitrous oxide (NO), polycyclic aromatic hydrocarbons (PAHs) microbial spores, pollen, allergens, etc. primarily contribute to IAQ deterioration. This review discusses the sources of major indoor air pollutants, molecular toxicity mechanisms, and their effects on cardiovascular, ocular, neurological, women, and foetal health. Additionally, contemporary strategies and sustainable methods for regulating and reducing pollutant concentrations are emphasized, and current initiatives to address and enhance IAQ are explored, along with their unique advantages and potentials. Due to their longer exposure times and particular physical characteristics, women and children are more at risk for poor indoor air quality. By triggering many toxicity mechanisms, including oxidative stress, DNA methylation, epigenetic modifications, and gene activation, indoor air pollution can cause a range of health issues. Low birth weight, acute lower respiratory tract infections, Sick building syndromes (SBS), and early death are more prevalent in exposed residents. On the other hand, the main causes of incapacity and early mortality are lung cancer, chronic obstructive pulmonary disease, and cardiovascular disorders. It's crucial to acknowledge anticipated research needs and implemented efficient interventions and policies to lower health hazards.

Effects of urban particulate matter on gut microbiome and partial schizophrenia-like symptoms in mice: Evidence from shotgun metagenomic and metabolomic profiling

BACKGROUND

Epidemiological evidence reported that particulate matter (PM) was associated with increased schizophrenia (SCZ) risk. Disturbance of gut microbiome was involved in SCZ. However, it remains unclear whether PM induces SCZ-like symptoms and how gut microbiome regulates them. Therefore, a multi-omics animal experiment was conducted to verify how urban PM induces SCZ-like behavior and altered gut microbiota and metabolic pathways.

METHODS

Using a completely random design, mice were divided into three groups: PM group, control group and MK801 group, which received daily tracheal instillation of PM solution, sterile PBS solution and intraperitoneal injection of MK801 (establish SCZ model), respectively. After a 14-day intervention, feces were collected for multi-omics testing (shotgun metagenomic sequencing and untargeted metabolomic profiling), followed by open field test, tail suspension test, and passive avoidance test. Besides, fecal microbiome of PM group and control group were transplanted into "pseudo-sterile" mice, then behavioral tests were conducted.

RESULTS

Similar to MK801 group, mice in PM group showed SCZ-like symptoms, including increased spontaneous activity, excitability, anxiety and decreased learning and spatial memory. PM exposure significantly increased the relative abundance of Verrucomicrobia and decreased that of Fibrobacteres et al. The metabolism pathways of estrogen signaling (estriol, 16-glucuronide-estriol and 21-desoxycortisol) and choline metabolism (phosphocholine) were significantly altered by PM exposure. Verrucomicrobia was negatively correlated with the level of estriol, which was correlated with decreased learning and spatial memory. Fibrobacteres and Deinococcus-Thermus were positively correlated with the level of phosphocholine, which was correlated with increased spontaneous activity, excitability and anxiety. Fecal microbiome transplantation from PM group mice reproduced excitability and anxiety symptoms.

CONCLUSIONS

Exposure to PM may affect composition of gut microbiome and alterations of estrogen signaling pathway and choline metabolism pathway, which were associated with partial SCZ-like behaviors. But whether gut microbiome regulates these metabolic pathways and behaviors remains to be determined.

Neurodevelopmental toxicity induced by PM2.5 Exposure and its possible role in Neurodegenerative and mental disorders

Recent extensive evidence suggests that ambient fine particulate matter (PM2.5, with an aerodynamic diameter ≤2.5 μm) may be neurotoxic to the brain and cause central nervous system damage, contributing to neurodevelopmental disorders, such as autism spectrum disorders, neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease, and mental disorders, such as schizophrenia, depression, and bipolar disorder. PM2.5 can enter the brain via various pathways, including the blood-brain barrier, olfactory system, and gut-brain axis, leading to adverse effects on the CNS. Studies in humans and animals have revealed that PM2.5-mediated mechanisms, including neuroinflammation, oxidative stress, systemic inflammation, and gut flora dysbiosis, play a crucial role in CNS damage. Additionally, PM2.5 exposure can induce epigenetic alterations, such as hypomethylation of DNA, which may contribute to the pathogenesis of some CNS damage. Through literature analysis, we suggest that promising therapeutic targets for alleviating PM2.5-induced neurological damage include inhibiting microglia overactivation, regulating gut microbiota with antibiotics, and targeting signaling pathways, such as PKA/CREB/BDNF and WNT/β-catenin. Additionally, several studies have observed an association between PM2.5 exposure and epigenetic changes in neuropsychiatric disorders. This review summarizes and discusses the association between PM2.5 exposure and CNS damage, including the possible mechanisms by which PM2.5 causes neurotoxicity.

Time trends and persistence in PM2.5 in 20 megacities: evidence for the time period 2018-2020

The degree of persistence in daily data for PM_2.5 in 20 relevant megacities such as Bangkok, Beijing, Mumbai, Calcutta, Canton, Dhaka, Delhi, Jakarta, London, Los Angeles, Mexico City, Moscow, New York, Osaka. Paris, Sao Paulo, Seoul, Shanghai, Tientsin, and Tokyo is examined in this work. The analysis developed is based on fractional integration techniques. Specifically, the differentiation parameter is used to measure the degree of persistence in the series under study, which collects data on daily measurements carried out from January 1, 2018, to December 31, 2020. The results obtained show that the estimated values for the differentiation parameter are restricted to the interval (0, 1) in all cases, which allows us to conclude that there is a mean reverting pattern and, therefore, transitory effects of shocks.

Short-term exposure to air pollution is an emerging but neglected risk factor for schizophrenia: A systematic review and meta-analysis

OBJECTIVE

This meta-analysis aimed to explore the association between short-term exposure to air pollution and schizophrenia (SCZ)1, and investigate the susceptible population and the lag characteristics of different pollutants.

METHODS

A systematic review and meta-analysis was conducted by searching PubMed, Cochrane, Web of Sciences, and CNKI for relevant literature published up to 28 Feb 2022. Meta-analysis was performed separately to investigate the association of ambient particulates (diameter ≤ 2.5 μm (PM2.5)2, 2.5 μm < diameter < 10 μm (PMC)3, ≤10μm (PM10)4) and gaseous pollutants (nitrogen dioxide (NO2)5, sulfur dioxide (SO2)6, carbon monoxide (CO)7) with SCZ. Relative risk (RR)8 per 10 μg/m3 increase in air pollutants concentration was used as the effect estimate. Subgroup analyses were conducted by age, gender, country, median pollutant concentration, and median temperature.

RESULTS

We identified 17 articles mainly conducted in Asia, of which 13 were included in the meta-analysis. Increased risk of SCZ was associated with short-term exposure to PM2.5 (RR: 1.0050, 95 % confidence interval (CI)9: 1.0017, 1.0083), PMC (1.0117, 1.0023, 1.0211), PM10 (1.0047, 1.0025, 1.0070), NO2 (1.0275, 1.0132, 1.0420), and SO2 (1.0288, 1.0146, 1.0432) exposure. Subgroup analyses showed that females may be more susceptible to SO2 and NO2, and the young seem to be more sensitive to PM2.5 and PM10. Gaseous pollutants presented the immediate risk, and particulates showed the delayed risk.

CONCLUSIONS

The present meta-analysis suggests that short-term exposure to PM2.5, PMC, PM10, SO2, and NO2 exposure may be associated with an elevated risk of SCZ.

Associations of Short-Term Exposure to Fine Particulate Matter with Neural Damage Biomarkers: A Panel Study of Healthy Retired Adults

Exposure to fine particulate matter (PM_2.5) is associated with various adverse health effects, such as respiratory and cardiovascular diseases. This study aimed to evaluate the association of PM_2.5 with neural damage biomarkers. A total of 34 healthy retirees were recruited from Xinxiang Medical University from December 2018 to April 2019. Concentrations of PM_2.5 constituents including 24 metals and nonmetallic elements and 6 ions, and 5 biomarkers of neural damage including brain-derived neurotrophic factor (BDNF), neurofilament light chain (NfL), neuron-specific enolase (NSE), protein gene product 9.5 (PGP9.5), and S100 calcium-binding protein B (S100B) in serum were measured. A linear mixed-effect model was employed to estimate the association of PM_2.5 and its constituents with neural damage biomarkers. Modification effects of glutathione S-transferase theta 1 gene (GSTT1) polymorphism, sex, education, and physical activity on PM_2.5 exposure with neural damage were explored. PM_2.5 and its key constituents were significantly associated with neural damage biomarkers. A 10 μg/m³ increase in PM_2.5 concentration was associated with 2.09% (95% CI, 39.3-76.5%), 100% (95% CI, 1.73-198%), and 122% (95% CI, 20.7-222%) increments in BDNF, NfL, and PGP9.5, respectively. Several constituents such as Cu, Zn, Ni, Mn, Sn, V, Rb, Pb, Al, Be, Cs, Co, Th, U, Cl^-, and F^- were significantly associated with NfL. The estimated association of PM_2.5 with NSE in GSTT1-sufficient volunteers was significantly higher than that in GSTT1-null volunteers. Therefore, short-term PM_2.5 exposure was associated with neural damage, and GSTT1 expression levels modified the PM_2.5-induced adverse neural effects.

Explaining the Association Between Urbanicity and Psychotic-Like Experiences in Pre-Adolescence: The Indirect Effect of Urban Exposures

Urban living is a growing worldwide phenomenon with more than two-thirds of people expected to live in cities by 2050. Although there are many benefits to living in an urban environment, urbanicity has also been associated with deleterious health outcomes, including increased risk for psychotic outcomes particularly when the urban exposure occurs in pre-adolescence. However, the mechanisms underlying this association is unclear. Here, we utilize one-year follow-up data from a large (N=7,979), nationwide study of pre-adolescence in the United States to clarify why urbanicity (i.e., census-tract population density) might impact psychotic-like experiences (PLE) by looking at the indirect effect of eight candidate urbanicity-related physical (e.g., pollution) and social (e.g., poverty) exposures. Consistent with other work, we found that of the evaluated exposures related to urbanicity, several were also related to increased number of PLE: PM2.5, proximity to roads, census-level homes at-risk for exposure to lead paint, census-level poverty, and census-level income-disparity. These same urban-related exposures were also related to the persistence of PLE after 1 year, but not new onset of PLE. Mediation analysis revealed that a substantial proportion the urbanicity-PLE association (number and persistence) could be explained by PM2.5 (23-44%), families in poverty (68-93%), and income disparity (67-80%). Together, these findings suggest that specific urban-related exposures contribute to the existence and maintenance, but not onset of PLE, which might help to explain why those in urban environments are disproportionately at-risk for psychosis and point toward areas for public health intervention.

Oxidative stress-mediated particulate matter affects the risk of relapse in schizophrenia patients: Air purification intervention-based panel study

Particulate matter (PM) exposure increased the risk of hospital admission and was related to symptoms of schizophrenia (SCZ). However, there are limited studies on the relationship between PM exposure and SCZ relapse risk, and the underlying biological mechanisms remain unclear. We designed an air purification intervention study under a 16-day real air purifier scenario and another 16-day sham air purifier scenario, with a 2-day washout period. Twenty-four chronic stable male patients were recruited. The oxidative stress biomarkers were measured including serum catalase (CAT), superoxide dismutase (SOD), total antioxidant capacity (T-AOC), malondialdehyde (MDA), and nitric oxide (NO). The relapse risk was evaluated by the early signs scale (ESS). Linear mixed effect models were fitted to establish the associations between PM exposure and ESS and oxidative stress. Mediation model was performed to explore the mediation effect of oxidative stress on the PM-ESS association. Higher concentrations of PM_2.5/PM₁₀ exposure were associated with an elevated risk of relapse of SCZ. For each 10 μg/m³ in PM_2.5 concentration, the scores of ESS and subscales of incipient psychosis (ESS-IP), depression/withdrawal (ESS-N), anxiety/agitation (ESS-A), and excitability/disinhibition (ESS-D) were increased by 4.112 (95% CI: 3.174, 5.050), 1.516 (95%CI: 1.178, 1.853), 1.143 (95%CI: 0.598, 1.689), 1.176 (95%CI: 0.727, 1.625) and 0.238 (95%CI: 0.013, 0.464), while logCAT, SOD and T-AOC were reduced by 0.039 U/ml (95% CI: 0.017, 0.060), 1.258 U/ml (95% CI: 0.541, 1.975), and 0.076 mmol/l (95% CI: 0.026, 0.126). In addition, pathways of "PM_2.5→T-AOC→ESS-A″ and "PM_2.5→T-AOC→ESS-D″ were found, with significant T-AOC mediated effects 15.70% (P = 0.02) and 52.99% (P = 0.04). Our findings suggest that PM may increase the risk of anxiety, depression, excitability, and incipient psychosis behaviors in SCZ patients, while reducing the function of the antioxidant system. The decrease of T-AOC may medicate the PM-ESS association in SCZ.

Elevated environmental PM2.5 increases risk of schizophrenia relapse: Mediation of inflammatory cytokines

BACKGROUND

Ecological epidemiology suggests that hospital admissions for schizophrenia are associated with an increased environmental PM_2.5, but no prospective study has verified this result, and the physiological mechanism is not clear.

METHODS

We used a repeated-measures design to prospectively assess the association of environmental PM_2.5 and the risk of relapse in schizophrenia, and used two linear mixed-effects models to explore possible mediating effects of immune cytokines on the premise of controlling confounders.

RESULTS

We import the data using EpiData software, and collate and analyze of the data using R software. The increase of PM_2.5 at lag0 had the greatest impact on the relapse of schizophrenia (for each 10 μg/m³ increase in PM_2.5, the relapse risk score increased by 1.504, that is to say, odds ratio (OR) = 4.500 (95% confidence interval (CI): 2.849-7.106，P < 0.001)), and cumulative effects lasted for four days with the maximum at the second day (for each 10 μg/m³ increase in PM_2.5, the relapse risk score increased by 1.301, OR = 3.673 (95%CI: 1.962-6.876，P < 0.001)). PM_2.5 exposure was statistically related to four symptom dimensions of early signs scale (ESS), and the symptoms most affected by the increased PM_2.5 were depression/withdrawal (ESSN) (OR = 1.990, 95%CI: 1.701-2.328), anxiety/agitation (ESS-A) (OR = 1.537, 95%CI: 1.340-1.763), initial psychosis (ESS-IP) (OR = 1.398, 95%CI: 1.151-1.697), and disinhibition (ESS-D) (OR = 1.235, 95%CI: 1.133-1.347). Furthermore, there are three statistically significant pathways in intermediary analysis: of PM_2.5 and relapse risk: "PM_2.5 → IL-17 → ESS", "PM_2.5 → IL-17 → ESS-A", and "PM_2.5 → IL-17 → ESS-N", and the intermediary ratio of IL-17 was 11.66%, 16.37% and 22.55%, respectively.

CONCLUSIONS

Increased environmental PM_2.5 is a risk factor for the relapse of schizophrenia. Early relapse identification and intervention based on clinical characteristics are of great significance for timely termination of relapse and slowing down of relapse.

Air Pollution and Central Nervous System Disease: A Review of the Impact of Fine Particulate Matter on Neurological Disorders

Background: It is widely known that the harmful effects of fine dust can cause various diseases. Research on the correlation between fine dust and health has been mainly focused on lung and cardiovascular diseases. By contrast, the effects of air pollution on the central nervous system (CNS) are not broadly recognized.

Findings: Air pollution can cause diverse neurological disorders as the result of inflammation of the nervous system, oxidative stress, activation of microglial cells, protein condensation, and cerebral vascular-barrier disorders, but uncertainty remains concerning the biological mechanisms by which air pollution produces neurological disease. Neuronal cell damage caused by fine dust, especially in fetuses and infants, can cause permanent brain damage or lead to neurological disease in adulthood.

Conclusion: It is necessary to study the air pollution–CNS disease connection with particular care and commitment. Moreover, the epidemiological and experimental study of the association between exposure to air pollution and CNS damage is critical to public health and quality of life. Here, we summarize the correlations between fine dust exposure and neurological disorders reported so far and make suggestions on the direction future research should take.

Air Pollution-Related Brain Metal Dyshomeostasis as a Potential Risk Factor for Neurodevelopmental Disorders and Neurodegenerative Diseases

Increasing evidence links air pollution (AP) exposure to effects on the central nervous system structure and function. Particulate matter AP, especially the ultrafine (nanoparticle) components, can carry numerous metal and trace element contaminants that can reach the brain in utero and after birth. Excess brain exposure to either essential or non-essential elements can result in brain dyshomeostasis, which has been implicated in both neurodevelopmental disorders (NDDs; autism spectrum disorder, schizophrenia, and attention deficit hyperactivity disorder) and neurodegenerative diseases (NDGDs; Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, and amyotrophic lateral sclerosis). This review summarizes the current understanding of the extent to which the inhalational or intranasal instillation of metals reproduces in vivo the shared features of NDDs and NDGDs, including enlarged lateral ventricles, alterations in myelination, glutamatergic dysfunction, neuronal cell death, inflammation, microglial activation, oxidative stress, mitochondrial dysfunction, altered social behaviors, cognitive dysfunction, and impulsivity. Although evidence is limited to date, neuronal cell death, oxidative stress, and mitochondrial dysfunction are reproduced by numerous metals. Understanding the specific contribution of metals/trace elements to this neurotoxicity can guide the development of more realistic animal exposure models of human AP exposure and consequently lead to a more meaningful approach to mechanistic studies, potential intervention strategies, and regulatory requirements.

Health and economic impacts of particulate matter pollution on hospital admissions for mental disorders in Chengdu, Southwestern China

The evidence for adverse effects of ambient particulate matter (PM) pollution on mental disorders (MDs) is limited, especially in developing countries. This study aimed to quantify both PM related health impacts and corresponding economic loses for overall and specific MDs in southwestern China. Data regarding 134,292 hospital admissions for MDs were collected from local Compulsory Medical Insurance Database in 2013-2017. A generalized additive model (GAM) was applied to estimate the exposure-response effects of PM pollution on hospital admissions for MDs. And the cost of illness method (COI) was adopted to further assess corresponding hospitalization costs and productivity loses. It was showed that PM pollution was significantly related to hospital admissions for overall and specific MDs. Each 10 μg/m³ increase in concentrations of PM₁₀ (particles with an aerodynamic diameters ≤10 μm), PM_2.5 (≤ 2.5 μm) and PMc (2.5 μm < c < 10 μm) at the cumulative lag03 day would be responsible for 3.25% (95%CI: 2.34-4.16%), 6.38% (95%CI: 4.79-7.97%), and 3.81% (95%CI: 2.13-5.50%) increments in daily hospital admissions for MDs, respectively. Stronger associations were observed in males, cool season and people over 45 years. During the study period, PM pollution brought 1453.18 million Yuan economic losses for overall MDs, accounting for 0.026% of local GDP. This study suggested that short-term exposure to PM pollution, especially to PM_2.5, was associated with increased hospital admissions for MDs in southwestern China. In addition, potential benefits of lowering PM concentrations are considerable.

Air pollutants and daily number of admissions to psychiatric emergency services: evidence for detrimental mental health effects of ozone

AIMS

Aim of the current study is to investigate the associations between daily levels of air pollutants (particulate matter, ozone, carbon monoxide, nitrogen dioxide) and daily admissions for mental disorders to the emergency department of two general hospitals in Umbria region (Italy).

METHODS

We collected data about daily admissions to psychiatric emergency services of two general hospitals, air pollutants' levels and meteorological data for the time period 1 January 2015 until 31 December 2016. We assessed the impact of an increase in air pollutants on the number of daily admissions using a time-series econometric framework.

RESULTS

A total of 1860 emergency department admissions for mental disorders were identified. We observed a statistically significant impact of ozone levels on daily admissions. The estimated coefficient of O3 is statistically significant at the 1% level. All other pollutants were not significantly associated with the number of daily admissions.

CONCLUSIONS

Short-term exposure to ozone may be associated with increased psychiatric emergency services admissions. Findings add to previous literature on existing evidence for air pollution to have an impact on mental health. Ozone may be considered a potential environmental risk factor for impaired mental health.

Developmental exposures to ultrafine particle air pollution reduces early testosterone levels and adult male social novelty preference: Risk for children's sex-biased neurobehavioral disorders

Epidemiological studies have reported associations of air pollution exposures with various neurodevelopmental disorders such as autism spectrum disorder (ASD), attention deficit and schizophrenia, all of which are male-biased in prevalence. Our studies of early postnatal exposure of mice to the ultrafine particle (UFP) component of air pollution, considered the most reactive component, provide support for these epidemiological associations, demonstrating male-specific or male-biased neuropathological changes and cognitive and impulsivity deficits consistent with these disorders. Since these neurodevelopmental disorders also include altered social behavior and communication, the current study examined the ability of developmental UFP exposure to reproduce these social behavior deficits and to determine whether any observed alterations reflected changes in steroid hormone concentrations. Elevated plus maze, social conditioned place preference, and social novelty preference were examined in adult mice that had been exposed to concentrated (10-20x) ambient UFPs averaging approximately 45 ug/m³ particle mass concentrations from postnatal day (PND) 4-7 and 10-13 for 4 h/day. Changes in serum testosterone (T) and corticosterone where measured at postnatal day (P)14 and approximately P120. UFP exposure decreased serum T concentrations on PND 14 and social nose-to-nose sniff rates with novel males in adulthood, suggesting social communication deficits in unfamiliar social contexts. Decreased sniff rates were not accounted for by alterations in fear-mediated behaviors and occurred without overt deficits in social preference, recognition or communication with a familiar animal or alterations in corticosterone. Adult T serum concentrations were positively correlated with nose to nose sniff rates. Collectively, these studies confirm another feature of male-biased neurodevelopmental disorders following developmental exposures to even very low levels of UFP air pollution that could be related to alterations in sex steroid programming of brain function.