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New Exam Developed to Detect Mercury Exposure in Harbor Seal Pups
· Confirmed
In Short: Veterinarians and researchers have developed a new neurological examination protocol for Pacific harbor seal pups to detect prenatal mercury exposure, according to a study published in Frontiers in Veterinary Science.
The standard neurological examination, designed for land-based quadrupeds, is not suitable for marine mammals like harbor seals. To address this, researchers at The Marine Mammal Center and Texas A&M University created a 33-test exam over two years.
Over 45 stranded pups were examined in care at the center over two consecutive years. The team revised their initial draft protocol after the first year.
The exam includes a variety of tests, such as observing the pups' reactions to a fish-head-on-a-string stimulus, which was found to be both useful and tasty.
Harbor seals are wild animals and primarily aquatic, requiring researchers to develop new methods to assess their neurological function.
Differences in ocean currents and environmental conditions can shape local food webs and prey composition, influencing maternal exposure and, in turn, the exposure their pups receive.
The research also includes people who consume the same or similar fish, allowing the team to examine contaminant exposure across species that share marine food resources.
Studying young animals can reveal exposures that started very early in life, providing insights into how prenatal mercury exposure may affect neurological development and an animal’s ability to survive in the wild.
The study involved 11,071 UK Biobank participants who each wore an accelerometer on their wrist with an integrated light sensor, which measures light exposure in units of lux, for seven days between 2013 and 2015.
Greater daytime light exposure was linked with up to a 41 percent lower risk of dementia.
Participants who experienced at least 42 minutes of bright daytime light at 5,000 lux or higher had an 17% lower risk than those with less exposure.
What's confirmed
- Researchers found that insufficient exposure to bright daytime light may be a stronger predictor of dementia than several established risk factors.
- 1 “Fish-head-on-a-string was a useful stimulus and, apparently, quite tasty.” Over 2 consecutive years, the team examined 45 stranded pups in care at the center.
- Studying young animals can therefore reveal exposures that started very early in life. 1 “Differences in ocean currents and environmental conditions can shape local food webs and prey composition,” Daniela A.
What's still developing
- Children exposed to extreme levels of “forever chemicals” before birth were significantly more likely to develop asthma, offering rare real-world evidence from a highly contaminated community while raising urgent questions about early-life exposure risks.
- To help resolve this question, the current study included a very high exposure group, unlike earlier research, which mostly focused on low-exposure populations.
- Environmental exposures, including air pollutants and infectious agents, have repeatedly been associated with increased asthma risk.
- No other exposure category showed any association, and no association was observed for wheeze, despite biological plausibility.
- Earlier epidemiological studies have produced mixed evidence, perhaps because they were relatively small, used parental-reported outcomes, and were limited to background PFAS exposure.
- Study: Prenatal exposure to per- and polyfluoroalkyl substances (PFAS) and incidence of asthma and wheeze in childhood: A register-based cohort study in Ronneby, Sweden.
- Such early-life exposure has been linked to immunosuppression, including a higher risk of childhood infections and a reduced antibody response to vaccination.
- However, despite its biological plausibility, the association of PFAS exposure with childhood asthma remains inconclusive, with conflicting results from epidemiological studies based on background PFAS exposure.
- A recent study in PLOS Medicine reports that very high prenatal PFAS exposure is associated with a higher incidence of childhood asthma.
- The second study, published in the journal Cephalalgia, investigated whether exposure to substances in tobacco smoke affects the regulation of genes in people with cluster headache.
- Inflammation, altered gene regulation, and exposure to substances in tobacco smoke may all contribute to the development of cluster headache.
- See the exact exposure conditions, lab results, patched versions, and mitigations for musl-based hosts and containers.