The Underlying Mechanism of Poisoning after the Accidental Inhalation of Aerosolised Waterproofing Spray.

Waterproofing sprays can cause acute respiratory symptoms after inhalation, including coughing and dyspnoea shortly after use. Here, we describe two cases where persons used the same brand of waterproofing spray product. In both cases the persons followed the instructions on the product and maximized the ventilation by opening windows and doors; however, they still became affected during the application of the product. Products with the same batch number as that used in one case were tested for their effect on respiration patterns of mice in whole-body plethysmographs and lung surfactant function inhibition in vitro. The product was used in spraying experiments to determine the particle size distribution of the aerosol, both using a can from one case and a can with an identical batch number. In addition, the aerosols in the mouse exposure chamber were measured. Aerosol data from a small-scale exposure chamber and data on the physical and temporal dimensions of the spraying during one case were used to estimate the deposited dose during the spraying events. All collected data point to the spraying of the waterproofing product being the reason that two people became ill, and that the inhibition of lung surfactant function was a key component of this illness.

Parental differential treatment of siblings linked with internalizing and externalizing behavior: A meta-analysis.

This meta-analysis linked relative and absolute parental differential treatment (PDT) with internalizing and externalizing behavior of children and adolescents. Multilevel meta-analysis data represented 26,451 participants based on 2890 effect sizes coming from 88 sources, nested within 43 samples. Participants were between 3.18 and 18.99 years of age (Mage = 12.64, SD = 3.89; 51.31% female; 82.23% White; 54.68% from the United States). Less-favored treatment (relative PDT) was linked to more internalizing and externalizing behavior. Additionally, greater differences in parenting between siblings (absolute PDT) were linked to more internalizing and externalizing behavior. Some links were moderated by other factors. For example, some effects were stronger when PDT was reported by children, and others, when siblings were closer in age.

Use of the dustiness index in combination with the handling energy factor for exposure modelling of nanomaterials.

The use of modelling tools in the occupational hygiene community has increased in the last years to comply with the different existing regulations. However, limitations still exist mainly due to the difficulty to obtain certain key parameters such as the emission rate, which in the case of powder handling can be estimated using the dustiness index (DI). The goal of this work is to explore the applicability and usability of the DI for emission source characterization and occupational exposure prediction to particles during nanomaterial powder handling. Modelling of occupational exposure concentrations of 13 case scenarios was performed using a two-box model as well as three nano-specific tools (Stoffenmanager nano, NanoSafer and GUIDEnano). The improvement of modelling performance by using a derived handling energy factor (H) was explored. Results show the usability of the DI for emission source characterization and respirable mass exposure modelling of powder handling scenarios of nanomaterials. A clear improvement in modelling outcome was obtained when using derived quartile-3 H factors with, 1) Pearson correlations of 0.88 vs. 0.52 (not using H), and 2) ratio of modelled/measured concentrations ranging from 0.9 to 10 in 75% cases vs. 16.7% of the cases when not using H. Particle number concentrations were generally underpredicted. Using the most conservative H values, predictions with ratios modelled/measured concentrations of 0.4-3.6 were obtained.

Correlation between inhibition of lung surfactant function in vitro and rapid reduction in tidal volume following exposure to plant protection products in mice.

Currently, testing of acute inhalation toxicity in animals is required for regulation of pesticide active ingredients and formulated plant protection products. The main outcome of the regulatory tests is "lethal concentration 50″ (LC50), i.e. the concentration that will kill 50% of the exposed animals. However, ongoing work aims to identify New Approach Methods (NAMs) to replace animal experiments. To this end, we studied 11 plant protection products, sold in the European Union (EU), for their ability to inhibit lung surfactant function in vitro in the constrained drop surfactometer (CDS). In vivo, inhibition of lung surfactant function can lead to alveolar collapse and reduction of tidal volume. Therefore, we also assessed changes in breathing patterns of mice during exposure to the same products. Six of the eleven products inhibited lung surfactant function, and six products reduced tidal volume in mice. In vitro inhibition of lung surfactant function predicted reduction in tidal volume in exposed mice with a sensitivity of 67% and a specificity of 60%. Two products were labelled as "harmful if inhaled", both inhibited surfactant function in vitro and reduced tidal volume in mice. Lung surfactant function inhibition in vitro predicted reduction in tidal volume for plant protection products to a lesser degree than for previously tested substances. This could owe to the requirement for rigorous testing of plant protection products prior to approval that might have selected against substances that could potentially inhibit lung surfactant, e.g. due to severe adverse effects during inhalation.

Genotoxicity in the absence of inflammation after tungsten inhalation in mice.

Tungsten is used in several applications and human exposure may occur. To assess its pulmonary toxicity, we exposed male mice to nose-only inhalation of tungsten particles at 9, 23 or 132 mg/m3 (Low, Mid and High exposure) (45 min/day, 5 days/week for 2 weeks). Increased genotoxicity (assessed by comet assay) was seen in bronchoalveolar (BAL) fluid cells at Low and High exposure. We measured acellular ROS production, and cannot exclude that ROS contributed to the observed genotoxicity. We saw no effects on body weight gain, pulmonary inflammation, lactate dehydrogenase or protein in BAL fluid, pathology of liver or kidney, or on sperm counts. In conclusion, tungsten showed non-dose dependent genotoxicity in the absence of inflammation and therefore interpreted to be primary genotoxicity. Based on genotoxicity, a Lowest Observed Adverse Effect Concentration (LOAEC) could be set at 9 mg/m3. It was not possible to establish a No Adverse Effect Concentration (NOAEC).

Pulmonary toxicity of molybdenum disulphide after inhalation in mice.

Molybdenum disulphide (MoS2) is a constituent of many products. To protect humans, it is important to know at what air concentrations it becomes toxic. For this, we tested MoS2 particles by nose-only inhalation in mice. Exposures were set to 13, 50 and 150 mg MoS2/m3 (=8, 30 and 90 mg Mo/m3), corresponding to Low, Mid and High exposure. The duration was 30 min/day, 5 days/week for 3 weeks. Molybdenum lung-deposition levels were estimated based on aerosol particle size distribution measurements, and empirically determined with inductively coupled plasma-mass spectrometry (ICP-MS). Toxicological endpoints were body weight gain, respiratory function, pulmonary inflammation, histopathology, and genotoxicity (comet assay). Acellular reactive oxygen species (ROS) production was also determined. The aerosolised MoS2 powder had a mean aerodynamic diameter of 800 nm, and a specific surface area of 8.96 m2/g. Alveolar deposition of MoS2 in lung was estimated at 7, 27 and 79 µg/mouse and measured as 35, 101 and 171 µg/mouse for Low, Mid and High exposure, respectively. Body weight gain was lower than in controls at Mid and High exposure. The tidal volume was decreased with Low and Mid exposure on day 15. Increased genotoxicity was seen in bronchoalveolar lavage (BAL) fluid cells at Mid and High exposures. ROS production was substantially lower than for carbon black nanoparticles used as bench-mark, when normalised by mass. Yet if ROS of MoS2 was normalised by surface area, it was similar to that of carbon black, suggesting that a ROS contribution to the observed genotoxicity cannot be ruled out. In conclusion, effects on body weight gain and genotoxicity indicated that Low exposure (13 mg MoS2/m3, corresponding to 0.8 mg/m3 for an 8-hour working day) was a No Observed Adverse Effect Concentration (NOAEC,) while effects on respiratory function suggested this level as a Lowest Observed Adverse Effect Concentration (LOAEC).

Sibling differences and parents' differential treatment of siblings: A multilevel meta-analysis.

The current study used meta-analysis to ask whether age differences, sex differences, and family size are linked to differences in parental treatment, as well as whether effect-sizes were moderated by the way parental differential treatment (PDT) was measured, who reported on the PDT, and the domain of PDT. Between August 2015 and November 2020, PsycINFO, Google Scholar, and PubMed Central were searched for articles relating to parental differential treatment; additionally, 13 sibling relationship scholars were contacted to collect unpublished analyses or unused data. Multilevel data came from 13,628 unique participants across 1,388 effect sizes nested within 66 sources (articles/raw data sets), nested within 23 unique samples (74% from North America; 26% from Western Europe). Multilevel meta-analysis conducted in R with the metafor package showed greater differences in parental treatment when siblings were further apart in age or a different sex. The main effects for age spacing, however, were moderated by several factors, particularly the domain of parenting. Specifically, age spacing was linked only to PDT based on control or autonomy granting, meaning when siblings were further apart in age, parents granted more autonomy to one sibling over another. Results were limited, however, by limited sample sizes at the sample level. Overall, findings suggest that parents may, in part, treat siblings differently because they are different to begin with. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

The family stress model and parents' differential treatment of siblings: A multilevel meta-analysis.

The family stress model (FSM) suggests that stress, particularly economic stress, hinders effective parenting. Expanding on the FSM, the present study examined not only the economic stress but also the general stress and several contexts that may promote stress-namely, physical health, mental health, socioeconomic status, employment status, and marital status. The present study also expanded the FSM to examine parenting of sibling groups. Ineffective parenting of sibling groups was conceptualized as greater parental differential treatment (PDT). A number of moderating variables were also considered. Multilevel meta-analysis models were used to test hypotheses. Across models, data came from 6,003 effect sizes, nested within 59 sources, nested within 16 unique samples (all coming from 8 published studies and 11 raw data sets). Results showed main effects for only parents' general stress and parents' mental health. More stress and poorer mental health were linked with greater amounts of PDT. Additionally, poorer physical health was linked to greater PDT but only when PDT involved positive parent-child interactions. As a whole, findings suggested that actual feelings of stress and psychological distress may show stronger links with PDT than contexts that merely have the potential to cause stress. Caution is warranted, however, as effect sizes were generally small and some models were based on predominantly Caucasian samples. Future research on the FSM and PDT should focus on actual experiences of stress and further consider the moderating role of domains of parenting. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Look Who's Talking: Mediums of Contact Among Mid-to Later-Life Siblings.

Adult siblings maintain contact and remain close to one another. The current study used participants recruited via Amazon Mechanical Turk (n = 491) to conduct regression analyses examining five methods of contact (in person, telephone, email, texting, and social media) predicting sibling closeness and conflict. Further, two- and three-way interactions assessed the role of sibling dyad composition (e.g., women with a sister and women with a brother). Results suggested that as contact in person, through social media, the telephone, or email increased, sibling closeness increased, while increased contact through email indicated less conflict. Assessing sibling dyad composition suggested as telephone contact increased, sibling closeness increased for all sibling dyads, especially for women with a sister compared to men with a brother. In-person and texting contacts were beneficial for women with a brother. Even in mid- to later-life, siblings connect through synchronous and asynchronous mediums, and this contact appears beneficial for sisters.

Nanoparticle Exposure and Workplace Measurements During Processes Related to 3D Printing of a Metal Object.

Metal 3D printing has many potential uses within prototyping and manufacturing. Selective laser melting (SLM) is a process that uses metal powders in the micrometer range as printing material. The particle release from the entire SLM printing process is not well-studied. While the 3D printing itself often occurs in a sealed chamber, activities related to the process can potentially release harmful metal particles to the indoor working environment through resuspension of the printing powder or via incident nanoparticles generated during printing. The objective of this study was to improve the understanding of particle exposure in work processes associated with 3D printing and potential needs for interventions by a case study conducted in a 3D printing facility. In this setting, direct release and dispersion of particles throughout the workspace from processes related to metal 3D printing was investigated. The release from five activities were studied in detail. The activities included post-printing cleaning, object annealing, and preparation of new base substrate for the next printing was. Three of the five measured activities caused particles number concentrations in the working environment to increase above background levels which were found to be 8·102 cm-3. Concentrations during chamber emptying and the open powder removal system (PRS) cleaning processes increased to 104 and 5·103 cm-3, respectively, whereas grinding activity increased number concentrations to 2.5·105 cm-3. Size distributions showed that particles were mainly smaller than 200 nm. Respirable mass concentrations were 50.4 µg m-3, collected on filters. This was corroborated by respirable mass measured with a DustTrak of 58.4 µg m-3. Respirable mass concentrations were below the occupational exposure limits in Denmark for an 8 h time-weighted average.

Acute Inhalation Toxicity After Inhalation of ZnO Nanoparticles: Lung Surfactant Function Inhibition In Vitro Correlates With Reduced Tidal Volume in Mice.

People can be exposed to zinc oxide (ZnO) by inhalation of consumer products or during industrial processes. Zinc oxide nanoparticle (NP) exposure can induce acute inhalation toxicity. The toxicological mechanisms underlying the acute effects on the lungs have long focused on the phagolysosomal dissolution of ZnO NPs in macrophages followed by the release of free Zn2+ ions. However, we postulate an alternative mechanism based on the direct interaction of ZnO NPs with the lung surfactant (LS) layer covering the inside of the alveoli. Therefore, we tested the effect of ZnO NPs and Zn2+ ions on the function of LS in vitro using the constrained drop surfactometer. We found that the ZnO NPs inhibited the LS function, whereas Zn2+ ions did not. To examine the role of lung macrophages in the acute toxicity of inhaled ZnO NPs, mice were treated with Clodrosome, a drug that depletes alveolar macrophages, or Encapsome, the empty carrier of the drug. After macrophage depletion, the mice were exposed to an aerosol of ZnO NPs in whole body plethysmographs recording breathing patterns continuously. Mice in both groups developed shallow breathing (reduced tidal volume) shortly after the onset of exposure to ZnO NPs. This suggests a macrophage-independent mechanism of induction. This study shows that acute inhalation toxicity is caused by ZnO NP interaction with LS, independently of NP dissolution in macrophages.

Parental Differential Treatment of Siblings and Adolescents' Health-Related Behaviors: The Moderating Role of Personality.

Youth who receive comparatively poorer parental treatment than a sibling are at risk for maladaptive behaviors in a variety of domains, but research has yet to examine links with adolescents' health-related behaviors nor consider how those links may vary based on adolescents' personality traits, namely conscientiousness and agreeableness. Two siblings (n = 590 adolescents; 53% female; Mage = 15.86, SD = 1.73) from 295 families reported on their differential conflict and closeness with their fathers and mothers as well as on their personality, sleep habits, exercise habits, and general health habits. Multilevel modeling revealed that, generally, the less conscientious adolescents had better health habits when they had comparatively warmer relationships with their mothers. Less conscientiousness adolescents may be less distressed by inequality in the family, and thus may experience positive effects of relatively better treatment.

The Longest-Lasting Relationship: Patterns of Contact and Well-Being Among Mid- to Later-Life Siblings.

OBJECTIVES: Adults in mid to later life experience shrinking social networks, which may hinder well-being. Siblings may be important sources of social contact. Yet, little is known about adults' patterns of contact with siblings and how contact is linked to well-being. METHOD: Participants included 491 adults from across the United States (M age = 58.96, SD = 6.25; 68% female) recruited online via Amazon Mechanical Turk; they reported on their contact with their sibling in person, over the phone, via email, texting, and social media. RESULTS: Latent class analysis found evidence for four patterns of contact (classes) among siblings: low, medium, high, and traditional. Those with high contact reported greater life satisfaction than those in the other groups. Those in the high group reported lower self-rated health when they recalled being treated less favorably, relative to their sibling, by their mother as children. DISCUSSION: These findings suggest that differing patterns of sibling contact exist among older adults. In some cases, contact may promote well-being. In other cases, more contact may serve as a reminder of hurtful or painful past family experiences related to mothers' differential treatment, in which case more contact may be linked to poorer health.

Social Withdrawal and Loneliness Among Older Adult Athletes: A Case for Playing Alone.

Some older adults may not receive social connection due to social withdrawal, potentially resulting in loneliness. The purpose of this study was to examine relationships between social withdrawal and loneliness, in the context of sports participation. The authors hypothesized that individuals who are more shy and avoidant would be more lonely than those who are less shy and avoidant, and that those who are unsocial would not necessarily be more lonely. The authors also hypothesized individual sport participation would further exacerbate loneliness over group sport participation. Results from participants in the Huntsman Senior Games (n = 374) indicated that as shyness, avoidance, and unsociability increased, loneliness increased as well. Furthermore, shy athletes in group sports reported higher levels of loneliness than those in individual sports. Although the authors seek to prevent individuals from being lonely in later life, there may be instances where removing oneself from a group is beneficial for mental health.

Companionship Patterns and Emotional States During Social Interactions for Adolescents With and Without Siblings.

For decades, researchers and the general public have debated whether children without siblings differ from children with siblings in ways that are meaningful for development. One area that is underexplored in the literature on only children versus children with siblings concerns time use and emotional states in alone time and in social interactions. Resource dilution theory and the prior literature suggests that adolescent only children and adolescents with siblings may differ in some social interactions, such as in time with parents, but not in others, such as in time alone, due to offsetting effects or the universality of certain experiences among adolescents. This study tested these arguments by comparing companionship patterns and four emotional states (happiness, sadness, stress, and meaningfulness) among adolescents (ages 15-18) without siblings (N= 465) and adolescents with siblings (N= 2513) in the nationally representative American Time Use Survey (2003-2017). Relative to adolescents with siblings, adolescents without siblings spent more time alone, similar amounts of time with peers, and more time exclusively with parents. Only children were not as happy when spending time alone and with peers as adolescents with siblings, but their emotions in these settings were not more negative or less meaningful. In most other social interactions, emotional states were similar between adolescents with and without siblings. These findings show that adolescents with and without siblings differed mainly in their companionship patterns within the household and in their levels of happiness when alone and with peers.

The Sisters' Advantage? Broader Autism Phenotype Characteristics and Young Adults' Sibling Support.

Siblings often oversee the well-being of an adult with autism spectrum disorder (ASD). The current study contributes to the literature by examining correlates of support provided to siblings in young adulthood in the context of the broader autism phenotype (BAP). Young adults (n = 866; Mage = 25.43, SD = 2.54; 55% female) reported on support provided to and the BAP characteristics of 1198 different siblings (Mage = 28.56, SD = 8.87; 50% female). Findings showed that young adults provided more emotional and practical support to sisters that they perceived to be higher in BAP characteristics. These findings suggest that sisters who have characteristics associated with ASD may be at an advantage in receiving support.

Indoor dispersion of airborne nano and fine particles: Main factors affecting spatial and temporal distribution in the frame of exposure modeling.

A particle exposure experiment inside a large climate-controlled chamber was conducted. Data on spatial and temporal distribution of nanoscale and fine aerosols in the range of mobility diameters 8-600 nm were collected with high resolution, for sodium chloride, fluorescein sodium, and silica particles. Exposure scenarios studied included constant and intermittent source emissions, different aggregation conditions, high (10 h-1 ) and low (3.5 h-1 ) air exchange rates (AERs) corresponding to chamber Reynolds number, respectively, equal to 1 × 105 and 3 × 104 . Results are presented and analyzed to highlight the main determinants of exposure and to determine whether the assumptions underlying two-box models hold under various scenarios. The main determinants of exposure found were the source generation rate and the ventilation rate. The effect of particles nature was indiscernible, and the decrease of airborne total number concentrations attributable to surface deposition was estimated lower than 2% when the source was active. A near-field/far-field structure of aerosol concentration was always observed for the AER = 10 h-1 but for AER = 3.5 h-1 , a single-field structure was found. The particle size distribution was always homogeneous in space but a general shift of particle diameter (-8% to +16%) was observed between scenarios in correlation with the AER and with the source position, presumably largely attributable to aggregation.

Effects of maternal inhalation of carbon black nanoparticles on reproductive and fertility parameters in a four-generation study of male mice.

BACKGROUND: Previous findings indicate that in utero exposure to nanoparticles may affect the reproductive system in male offspring. Effects such as decreased sperm counts and testicular structural changes in F1 males have been reported following maternal airway exposure to carbon black during gestation. In addition, a previous study in our laboratory suggested that the effects of in utero exposure of nanoparticles may span further than the first generation, as sperm content per gram of testis was significantly lowered in F2 males. In the present study we assessed male fertility parameters following in utero inhalation exposure to carbon black in four generations of mice. RESULTS: Filter measurements demonstrated that the time-mated females were exposed to a mean total suspended particle mass concentration of 4.79 ± 1.86 or 33.87 ± 14.77 mg/m3 for the low and high exposure, respectively. The control exposure was below the detection limit (LOD 0.08 mg/m3). Exposure did not affect gestation and litter parameters in any generation. No significant changes were observed in body and reproductive organ weights, epididymal sperm parameters, daily sperm production, plasma testosterone or fertility. CONCLUSION: In utero exposure to carbon black nanoparticles, at occupationally relevant exposure levels, via maternal whole body inhalation did not affect male-specific reproductive, fertility and litter parameters in four generations of mice.

Contributions of Mainstream Sexual Media Exposure to Sexual Attitudes, Perceived Peer Norms, and Sexual Behavior: A Meta-Analysis.

PURPOSE: Decades of research have examined the impact of exposure to nonexplicit portrayals of sexual content in media. There is only one meta-analysis on this topic, which suggests that exposure to "sexy media" has little to no effect on sexual behavior. There are a number of limitations to the existing meta-analysis, and the purpose of this updated meta-analysis was to examine associations between exposure to sexual media and users' attitudes and sexual behavior. METHODS: A thorough literature search was conducted to find relevant articles. Each study was coded for associations between exposure to sexual media and one of six outcomes including sexual attitudes (permissive attitudes, peer norms, and rape myths) and sexual behaviors (general sexual behavior, age of sexual initiation, and risky sexual behavior). RESULTS: Results from 59 studies, involving 394 effect sizes, revealed that exposure to sexual media had a small but significant effect on both sexual attitudes and behaviors; the effect size was comparable to other media effects meta-analyses. Effects were stronger for adolescents than emerging adults. In addition, effects were stronger for boys than girls and for white participants compared with black participants. CONCLUSION: This study suggests that exposure to nonexplicit sexual media is associated with both sexual attitudes and behavior, particularly during adolescence. Implications for parents, media producers, and researchers are discussed.

Maternal inhalation of carbon black nanoparticles induces neurodevelopmental changes in mouse offspring.

BACKGROUND: Engineered nanoparticles are smaller than 100 nm and designed to improve or creating even new physico-chemical properties. Consequently, toxicological properties of materials may change as size reaches the nm size-range. We examined outcomes related to the central nervous system in the offspring following maternal inhalation exposure to nanosized carbon black particles (Printex 90). METHODS: Time-mated mice (NMRI) were exposed by inhalation, for 45 min/day to 0, 4.6 or 37 mg/m3 aerosolized carbon black on gestation days 4-18, i.e. for a total of 15 days. Outcomes included maternal lung inflammation (differential cell count in bronchoalveolar lavage fluid and Saa3 mRNA expression in lung tissue), offspring neurohistopathology and behaviour in the open field test. RESULTS: Carbon black exposure did not cause lung inflammation in the exposed females, measured 11 or 28-29 days post-exposure. Glial fibrillary acidic protein (GFAP) expression levels were dose-dependently increased in astrocytes around blood vessels in the cerebral cortex and hippocampus in six weeks old offspring, indicative of reactive astrogliosis. Also enlarged lysosomal granules were observed in brain perivascular macrophages (PVMs) in the prenatally exposed offspring. The number of parvalbumin-positive interneurons and the expression levels of parvalbumin were decreased in the motor and prefrontal cortices at weaning and 120 days of age in the prenatally exposed offspring. In the open field test, behaviour was dose-dependently altered following maternal exposure to Printex 90, at 90 days of age. Prenatally exposed female offspring moved a longer total distance, and especially males spent significantly longer time in the central zone of the maze. In the offspring, the described effects were long-lasting as they were present at all time points investigated. CONCLUSION: The present study reports for the first time that maternal inhalation exposure to Printex 90 carbon black induced dose-dependent denaturation of PVM and reactive astrocytes, similarly to the findings observed following maternal exposure to Printex 90 by airway instillation. Of note, some of the observed effects have striking similarities with those observed in mouse models of neurodevelopmental disorders.