NIEHS-funded researchers uncovered a mechanism through which nucleotide repeat expansions — specifically the CAG repeat expansion named for its repeating cytosine, adenine, and guanine nucleotides — contribute to neurological diseases. They found that a protein referred to as TRMT61A attached a methyl group to a nucleotide within the CAG repeat RNA, creating a new molecule called N1-methyladenosine. The findings may inform therapeutic interventions for neurodegenerative diseases resulting from CAG repeat expansion. Read the full summary.

Exposure to polybrominated diphenyl ethers (PBDEs) may suppress immune response in children with autism, according to an NIEHS-funded study. The researchers found associations between several PBDE chemicals and reduced T-cell function only in children with autism. T cells are a type of white blood cell that establishes and maintains immune responses. According to the authors, PBDEs have a more detrimental effect on the immune responses of children with autism, and the toxicant BDE-49 may be specifically damaging to the immune system. Read the full summary.

A combination of limestone and a bone-like mineral called hydroxyapatite can remove arsenic and uranium from water, according to an NIEHS-funded study. Pollution of local water sources by metals associated with hard rock mining is a major concern among Native American communities in the western U.S. Remediation strategies that use these natural materials could protect communities at risk of metal exposures. Read the full summary.

Nearly 57,000 cases of preterm birth a year may be attributable to phthalate exposures, according to a study funded by NIEHS and others. Phthalates are synthetic chemicals widely used in consumer products, such as vinyl flooring and personal care items. The results suggest substantial opportunities for phthalate exposure prevention and indicate a need to regulate newer replacement chemicals with similar properties. Read the full summary.

Exposure to heavy metals may be linked to earlier menopause in middle-aged women, NIEHS-researchers reported. The study is the first to assess how metals affect levels of anti-Müllerian hormone (AMH) over time in women approaching menopause. These results indicate that certain heavy metals may act as ovarian toxicants by depleting ovarian reserve in women approaching menopause. Read the full summary.

Exposure to ash from wildfires that occur where nature meets development may enhance the growth of more infectious marine bacteria, NIEHS-funded researchers reported. Their findings provide insight into how extreme weather associated with climate change may contribute to the spread of more infectious strains of Vibrio vulnificus, a bacterium responsible for most seafood-related deaths in the U.S. Read the full summary.

NIEHS-funded researchers developed a new cell-based approach for studying how environmental contaminants, like arsenic, interact with our genes to affect health. The results could help identify molecular pathways underlying genetic sensitivity and resistance to environmental toxicants and minimize reliance on animal testing in chemical risk assessments. Read the full summary.

Arsenic exposure from private wells declined among American Indian communities that received free kitchen faucet filters and periodic health check-ins through phone calls and home visits, according to NIEHS-funded researchers. The results show that point-of-use filter installation, combined with mobile health check-ins, can reduce arsenic exposure, according to the authors. Given that public health interventions involving in-person visits can be costly and difficult to implement in rural areas, the findings could inform feasible arsenic mitigation programs among other private well users. Read the full summary.

Prenatal fluoride exposure may increase the risk of neurobehavioral problems among U.S. children, according to NIEHS-funded researchers. This is the first U.S.-based study to examine the relationship between fluoride exposure during pregnancy and neurobehavioral outcomes in childhood. Read the full summary.

Tampons may contain traces of certain metals, according to a study funded in part by NIEHS. According to the researchers, this study is one of the first to measure concentrations of metals in tampons. All samples contained levels of toxic metals, including cadmium, vanadium, and lead. They noted it is unclear if metals can transfer from tampons into the body to potentially cause harm. Read the full summary and related story.

A new approach for screening environmental contaminants revealed certain organic pollutants can negatively affect male fertility, according to an NIEHS-funded study. This is the first human study to show that etridiazole, a common fungicide, and N-nitrosodiethylamine, which can be a drinking water contaminant due to its wide range of industrial applications, may harm human male reproductive health. Read the full summary.

NIEHS-funded researchers identified a type of bacteria that can destroy specific per- and polyfluoroalkyl substances (PFAS). Called Acetobacterium, the microorganisms are commonly found in wastewater environments throughout the world and could potentially be optimized and used as a cost-effective and environmentally friendly approach to remediate sites contaminated with the persistent chemical. PFAS are used in products such as nonstick cookware and firefighting foams. Read the full summary.

Researchers funded by NIEHS have discovered two massive proteins essential to the structure of an algal toxin responsible for large fish kills. The findings provide a model for studying other marine algal genes and associated toxins that are harmful to human health. Read the full summary.

Exposure to mixtures of PFAS chemicals may pose a greater health risk than exposure to a single PFAS alone, NIEHS-funded researchers found. According to the authors, the study results have important implications for risk assessment and suggest that PFAS should be regulated as mixtures. Read the full summary.

Exposure to extreme heat in early pregnancy may increase the risk of neural tube defects (NTDs), according to research funded by NIEHS. NTDs such as spina bifida and anencephaly are severe birth defects that affect brain and spine development in the first month of pregnancy. The study results highlight the potential for rising global temperatures to increase rates of serious birth defects. Read the full summary.

A general framework called ANCOM-BC2 enables multigroup analysis of compositions of microbiomes, which are collections of microbes, according to NIEHS researchers and their collaborators. ANCOM-BC2 allows researchers to infer patterns in microbial abundance over ordered categories of exposure variables. An accompanying free downloadable software package is available. Read the full summary.

A novel computational approach called MIBCOVIS could enable deeper insights into complicated biological systems, according to NIEHS researchers and their collaborators. This powerful framework can be applied to single-cell and non-single-cell data from various scientific fields. Read the full summary.

Myositis-associated autoantibodies (MAAs) are a prevalent marker of poor prognosis for patients with juvenile myositis, according to NIEHS researchers and their collaborators. Myositis is a medical condition characterized by inflammation affecting the muscles. According to the authors, prospective studies are needed to determine whether early detection of MAAs may lead to improved outcomes. Read the full summary.

Using talcum powder as an intimate care product may be associated with an increased risk of developing ovarian cancer, according to NIEHS researchers and their collaborators. The findings provide valuable insights into current discussions concerning the safety of intimate care products. According to the authors, further research is needed to identify specific chemicals in intimate care products that may affect cancer risk. Read the full summary and related article.

Exposure to chemicals called phthalates during pregnancy may contribute to racial and ethnic disparities in preterm birth, according to NIEHS researchers and their collaborators. Compared with White participants, mean phthalate metabolite concentrations were consistently higher among Black and Hispanic/Latina participants. According to the authors, these findings support the need to reduce phthalate exposures among systematically marginalized people. Read the full summary.

The chromatin landscape of neural progenitor cells (NPCs) is established by activity of the Brahma-related gene 1 (BRG1)-associated factor (BAF) complex, according to NIEHS researchers. Loss of BRG1 expression in NPCs within the developing brain could promote the acquisition of inappropriate cell fates concomitant with tumor initiation or malignant conversion. This potentially aberrant NPC specification could be a contributing factor to the aggressiveness and poor prognoses of certain brain tumors. Read the full summary.

Insights into the high-resolution structure of molecules called mtSSB and ssDNA may lead to new therapies for mitochondrial diseases, according to NIEHS researchers. The identification and characterization of SSBP1 mutations is crucial for the diagnosis and management of mitochondrial diseases, and further research into the mechanisms underlying these mutations could lead to the development of novel therapies. Read the full summary.

Thromboxane A2 (TXA2) can dampen the immune response in the allergic lung, which may have important therapeutic consequences, according to NIEHS researchers and their collaborators. These results help explain the failure of anti-thromboxane therapies and suggest that targeting the TXA2/TP receptor signaling pathway may lead to the development of novel asthma treatments. Read the full summary.

State-of-the-art metagenomic sequencing has revealed specific microorganisms in indoor dust related to pulmonary function and airway inflammation, according to NIEHS researchers and their collaborators. This comprehensive investigation of microbial signatures in house dust and adult respiratory outcomes could help elucidate complex mechanisms of chronic exposure to house dust and respiratory health across the life course. Read the full summary.

The hormones estrogen and progesterone regulate gene expression differently during two stages of the mouse reproductive cycle, according to NIEHS researchers. The findings could enhance the understanding of how hormone regulation of genes contributes to both health and disease. Read the full summary.

New experimental data could significantly enhance knowledge of several types of PFAS and their potential health effects, according to researchers from the Division of Translational Toxicology. The study could enable refined modeling and human health evaluations across this important set of emerging contaminants. Read the full summary.

A recent commentary by researchers from the Division of Translational Toxicology promotes a better understanding of clustering and classification approaches (CCAs) in toxicity research and risk assessment, and advocates for increased use within international collaborations. Interdisciplinary collaboration and implementation of recommendations presented in the commentary could play an important role in enhancing the use of CCAs across diverse fields. Read the full summary.

Zebrafish experiments across different laboratories produce generally consistent results regarding test substances’ activity but not their potencies, according to researchers from the Division of Translational Toxicology. The lessons learned from the study emphasize the potential benefits of standardized testing protocols for the zebrafish research community interested in toxicology testing. Read the full summary.

A new analysis of the genetic makeup of rat brain and heart tumors highlights morphological and molecular similarities to those found in humans, according to researchers from the Division of Translational Toxicology. This is the first study demonstrating genetic alterations in rat tumors resulting from life-time exposure to radiofrequency radiation (RFR). Read the full summary.

A first-of-its-kind systematic evidence map allows researchers to evaluate studies exploring the link between personal care products (PCPs) and early onset of puberty, according to researchers from the Division of Translational Toxicology. The final data were used to create interactive visuals, which are available for download from an interactive dashboard. Read the full summary and related article.