Methylmercury risk and awareness among American Indian women of childbearing age living on an inland northwest reservation

Risk communication and perceptions about lead ammunition and Inuit health in Nunavik, Canada

Lead ammunition is commonly used to hunt waterfowl and other wildlife in the Arctic. Hunting with lead is problematic because the toxicant can be transferred to the consumer. Therefore, it is critical to evaluate perceptions and awareness of the risks associated with using lead ammunition among Arctic populations. Results of the Nunavik Child Development Study (a longitudinal health study gathering information on health and well-being among Inuit in Nunavik, Canada) included advice to eliminate the use of lead ammunition in hunting practices. We surveyed 112 Nunavik residents (93 women; 18 men) about their awareness of lead related messages, use of lead ammunition and risk perceptions about contaminants. Sixty-seven participants (59.8%) reported there was an active hunter in their household. We found that only 27% of participants had heard or seen the messages about reducing lead ammunition. After participants viewed the Nunavik Child Development Study messages about lead, 44% stated they would stop using lead ammunition. However, 28% indicated that they would continue using lead ammunition. We conclude that, while messages had an overall positive effect, further study is required to understand why people continue to use lead ammunition.

Fish Consumption and Advisory Awareness among a Representative Sample of Wisconsin Adults, 2017-2019

PURPOSE

To examine fish consumption patterns and fish advisory awareness among Wisconsin adults.

DESIGN

Cross-sectional data from population-based survey. Setting: 2017-2019 Wisconsin Behavioral Risk Factor Surveillance System (BRFSS), supplemental fish module.

SUBJECTS

15,757 Wisconsinites aged ≥18 years. Annual response rates ranged 46.1-53.3%.

MEASURES

Fish consumption, advisory awareness, background and demographic characteristics.

ANALYSIS

Weighted binary and multinomial logistic regression.

RESULTS

Most Wisconsinites reported eating fish in the past 30 days, with approximately half (49.8%) consuming less than one fish meal per week. One-fifth of adults reported consuming sportfish. Women were less likely to eat any fish (POR_adj = .6, 95% CI: .5-.7) and sportfish than men (POR_adj = .7, 95% CI: .6-.8). The majority (76.7%) of sportfish consumers were aware of fish advisories. However, women (POR_adj = .7, 95% CI: .5-.9) and black, Indigenous, and people of color (BIPOC) (POR_adj = .4, 95% CI: .2-.7) sportfish consumers were less likely to be aware of fish advisories. Compared to adults aged 18-34 years, adults ≥55 years were twice as likely to eat 1-2 fish meals (vs. less than 1 fish meal) per week (POR_adj = 2.3, 95% CI: 1.8-2.9).

CONCLUSION

Findings indicate that half of all Wisconsinites consumed less fish than recommended by Wisconsin fish advisories, and women and BIPOC respondents were less likely to be aware of advisories. Educational efforts are needed to improve fish consumption habits.

p62/sequestosome 1 attenuates methylmercury-induced endoplasmic reticulum stress in mouse embryonic fibroblasts

Methylmercury (MeHg) is a hazardous environmental pollutant that causes serious toxicity in humans and animals, as well as proteotoxic stress. In our previous study, we found that MeHg induces the expression of p62/sequestosome 1 (p62) that selectively targets ubiquitinated proteins for degradation via autophagy, and that p62 might protect cells against MeHg toxicity. To further investigate the role of p62 in MeHg-induced stress responses, we evaluated the role of p62 in MeHg-induced endoplasmic reticulum (ER) stress in p62 knockout (p62KO) mouse embryonic fibroblasts (MEFs). Treatment of wild-type (WT) MEFs were treated with MeHg (1 μM) increased mRNA levels of Chop encoding C/EBP homologous protein, Trib3 encoding Tribbles homolog 3, and Dnajb9 encoding DnaJ heat-shock protein family (Hsp40) member B9 increased, suggesting that ER stress is elicited by MeHg stress. Additionally, p62KO MEFs treated with MeHg showed a higher mRNA expression of Chop and Trib3 relative to that in WT MEFs. Furthermore, knock-in of GFP-p62 to p62KO cells diminished the Chop and Trib3 induction responses to MeHg stress and resulted in a higher cell viability than that of p62KO MEFs. These results suggest that the protective role of p62 against MeHg toxicity is partly mediated by suppressing the ER stress response.

Communicating Environmental Health Risks with Indigenous Populations: A Systematic Literature Review of Current Research and Recommendations for Future Studies

Indigenous populations are recognized as a group who are potentially vulnerable to environmental health hazards due to their intimate relationship with and reliance on local environments for aspects of culture, health, and well-being. In many circumstances barriers to effective communication and health risk management are linked to cultural, economic, and geographic factors. A systematic literature review was conducted to consolidate peer-reviewed research on the communication of environmental health risks with Indigenous populations. The comprehensive literature review procedures included searching databases and key journals that represented various fields in communication, environmental health, and Indigenous studies. The review yielded a total of 4,469 potential articles and a total of 13 of these manuscripts met the inclusion criteria. The 13 articles were analyzed to identify lessons learned for effective risk communication. Factors that influence successful risk communication strategies with Indigenous populations on this topic include: (1) developing messages that are congruent with the populations' cultural beliefs and understanding of the environment; (2) including Indigenous populations in message design and delivery; (3) using credible and trustworthy spokespeople in message delivery; (4) identifying and utilizing effective communication materials and channels; and (5) ensuring that messages are understandable to the target audience. Gaps in the literature include the lack of longitudinal studies that empirically measure changes in perception, awareness and behavior, as well as a general lack of theory-based research. Results from this review provide directions for future work to help guide the development of more effective health risk communication research and strategies with Indigenous populations.

Feasibility of Hair Collection for Cortisol Measurement in Population Research on Adolescent Health

BACKGROUND

Black-White disparities in adolescent health are widespread and thought to be explained, in part, by exposure to chronic stress. Cortisol assayed from hair is increasingly recognized as a valid and reliable measure for chronic physiological stress, but the feasibility of collecting hair among large probability samples of diverse adolescents is unknown.

PURPOSE

The aim of the study was to investigate participation in hair collection for cortisol analyses in a probability sample of racially and socioeconomically diverse adolescents, including the extent to which sociodemographic factors and adverse exposures were associated with participation.

METHODS

The study included a probability sample of 516 adolescents conducted in conjunction with a prospective cohort study on adolescent health. Data were collected over 1 week via in-home interviews, ecological momentary assessment, global positioning system methods, and in-home hair collection at the end of the week.

RESULTS

Of the 516 eligible youth, 471 (91.3%) participated in the hair collection. Of the 45 youth who did not provide hair samples, 18 had insufficient hair, 25 refused, and 2 did not participate for unknown reasons. Multivariable logistic regression results indicated that non-Hispanic Black youth were less likely than their non-Hispanic White peers to participate due to insufficient hair or refusal (OR = 0.24, 95% CI [0 .09, 0.60]). Despite lower rates of participation, the proportion of Black youth in the participating sample was representative of the study area. No significant differences in participation were found by other sociodemographic characteristics or adverse exposures.

CONCLUSIONS

Hair collection for cortisol measurement is feasible among a probability sample of racially and socioeconomically diverse adolescents. Hair cortisol analyses may accelerate research progress to understand the biological and psychosocial bases of health disparities.

A qualitative exploration of fishing and fish consumption in the Gullah/Geechee culture

The Gullah/Geechee (G/G) heritage is rooted in a culture largely dependent on fish and seafood as a primary food source. Research suggests that African-American (AA) fishers in the Southeastern US consume larger amounts of fish, potentially exposing them to higher environmental contaminant levels. This in-depth study was conducted to explore G/G and AA Sea Island attitudes, perceptions, and cultural beliefs about fishing in one urban and two rural South Carolina coastal counties. Results indicated that study participants in rural counties had slightly different perspectives of fishing (e.g. fishing as an essential dietary supplement) than in urban counties where fishing was viewed more as relaxation. Major misperceptions existed in all counties between fish consumption advisories related to pollution versus harvesting restrictions associated with fishing regulations. Providing clear, culturally tailored health messages regarding fish advisories will promote more informed choices about fish consumption that will minimize potential exposures to environmental pollutants.

Fish Consumption Patterns and Mercury Advisory Knowledge Among Fishers in the Haw River Basin

BACKGROUND

Fish consumption has numerous health benefits, with fish providing a source of protein as well as omega-3 fatty acids. However, some fish also contain contaminants that can impair human health. In North Carolina, the Department of Health and Human Services has issued fish consumption advisories due to methylmercury contamination in fish. Little is known about local fishers' consumption patterns and advisory adherence in North Carolina.

METHODS

We surveyed a consecutive sample of 50 fishers (74.6% positive response rate) who reported eating fish caught from the Haw River Basin or Jordan Lake. They provided information on demographic characteristics, species caught, and the frequency of local fish consumption. Additionally, fishers provided information on their knowledge of fish consumption advisories and the impact of those advisories on their fishing and fish consumption patterns.

RESULTS

The majority of participants were male (n = 44) and reported living in central North Carolina. Catfish, crappie, sunfish, and large-mouth bass were consumed more frequently than other species of fish. Of the fishers surveyed, 8 reported eating more than 1 fish meal high in mercury per week, which exceeds the North Carolina advisory recommendation. Most participants (n = 32) had no knowledge of local fish advisories, and only 4 fishers reported that advisories impacted their fishing practices.

LIMITATIONS

We sampled 50 fishers at 11 locations. There is no enumeration of the dynamic population of fishers and no way to assess the representativeness of this sample.

CONCLUSIONS

Additional outreach is needed to make local fishers aware of fish consumption advisories and the potential health impacts of eating high-mercury fish, which may also contain other persistent and bioaccumulative toxins.

Which fish should I eat? Perspectives influencing fish consumption choices

BACKGROUND

Diverse perspectives have influenced fish consumption choices.

OBJECTIVES

We summarized the issue of fish consumption choice from toxicological, nutritional, ecological, and economic points of view; identified areas of overlap and disagreement among these viewpoints; and reviewed effects of previous fish consumption advisories.

METHODS

We reviewed published scientific literature, public health guidelines, and advisories related to fish consumption, focusing on advisories targeted at U.S. populations. However, our conclusions apply to groups having similar fish consumption patterns.

DISCUSSION

There are many possible combinations of matters related to fish consumption, but few, if any, fish consumption patterns optimize all domains. Fish provides a rich source of protein and other nutrients, but because of contamination by methylmercury and other toxicants, higher fish intake often leads to greater toxicant exposure. Furthermore, stocks of wild fish are not adequate to meet the nutrient demands of the growing world population, and fish consumption choices also have a broad economic impact on the fishing industry. Most guidance does not account for ecological and economic impacts of different fish consumption choices.

CONCLUSION

Despite the relative lack of information integrating the health, ecological, and economic impacts of different fish choices, clear and simple guidance is necessary to effect desired changes. Thus, more comprehensive advice can be developed to describe the multiple impacts of fish consumption. In addition, policy and fishery management interventions will be necessary to ensure long-term availability of fish as an important source of human nutrition.

Communicating fish consumption advisories in California: what works, what doesn't

State agencies face many challenges in creating sport fish consumption advisories that can be readily understood by diverse populations. In this study, our objectives were to identify barriers to understanding consumption advisories and recommend more effective approaches for communicating advisory concepts. We conducted key informant interviews with demographically diverse consumers of sport fish from the Sacramento-San Joaquin Delta watershed in California to explore how intended audiences perceive consumption advisories and identify factors that influence comprehension. Some barriers to communication included the use of portion sizes that departed from commonly consumed amounts, poorly understood terminology, misleading category headings, and ineffective visual tools. Comprehension was enhanced when advisory information did not contradict existing beliefs about fish or fish consumption, and when advisories provided information about contaminant levels in specific kinds of fish. Using certain methods, such as portion sizes that reflect commonly consumed amounts, mercury meters to convey contaminant levels, three advice categories (e.g., high, medium, low), and population definitions that identify specific age ranges, improved the clarity of advisory concepts for intended audiences.

Awareness and knowledge of methylmercury in fish in the United States

In the 1970s several states in the Great Lakes region became concerned about mercury contamination in lakes and rivers and were the first to issue local fish consumption advisories. In 2001, the Food and Drug Administration (FDA) advised pregnant women, nursing mothers, young children, and women who may become pregnant not to consume shark, swordfish, king mackerel, and tilefish and recommended that these women not exceed 12 ounces of other fish per week. In 2004, FDA reissued this advice jointly with the U.S. Environmental Protection Agency (EPA) and modified it slightly to provide information about consumption of canned tuna and more details about consumption of recreationally caught fish. Though several studies have examined consumers' awareness of the joint FDA and EPA advisory as well as different state advisories, few used representative data. We examined the changes in awareness and knowledge of mercury as a problem in fish using the pooled nationally representative 2001 and 2006 Food Safety Surveys (FSS) with sample sizes of 4482 in 2001 and 2275 in 2006. Our results indicated an increase in consumers' awareness of mercury as a problem in fish (69% in 2001 to 80% in 2006, p<.001). In our regression models, we found that in both years, parents having children less than 5 years of age were more aware of mercury in fish and knowledgeable about the information contained in the national advisories about mercury in fish (p<.01) than other adults. In both 2001 and 2006, women of childbearing age (aged 18-45) were less aware and knowledgeable about this information than other women. However, women of all age groups had larger gains in awareness and knowledge than their male counterparts during this time. Participants' race, education, income, region, fish preparation experiences, having a foodborne illness in the past year, and risk perceptions about the safety of food were significant predictors of their awareness and knowledge.

Methylmercury induces acute oxidative stress, altering Nrf2 protein level in primary microglial cells

The neurotoxicity of methylmercury (MeHg) is well documented in both humans and animals. MeHg causes acute and chronic damage to multiple organs, most profoundly the central nervous system (CNS). Microglial cells are derived from macrophage cell lineage, making up approximately 12% of cells in the CNS, yet their role in MeHg-induced neurotoxicity is not well defined. The purpose of the present study was to characterize microglial vulnerability to MeHg and their potential adaptive response to acute MeHg exposure. We examined the effects of MeHg on microglial viability, reactive oxygen species (ROS) generation, glutathione (GSH) level, redox homeostasis, and Nrf2 protein expression. Our data showed that MeHg (1-5 microM) treatment caused a rapid (within 1 min) concentration- and time-dependent increase in ROS generation, accompanied by a statistically significant decrease in the ratio of GSH and its oxidized form glutathione disulfide (GSSG) (GSH:GSSG ratio). MeHg increased the cytosolic Nrf2 protein level within 1 min of exposure, followed by its nuclear translocation after 10 min of treatment. Consistent with the nuclear translocation of Nrf2, quantitative real-time PCR revealed a concentration-dependent increase in the messenger RNA level of Ho-1, Nqo1, and xCT 30 min post MeHg exposure, whereas Nrf2 knockdown greatly reduced the upregulation of these genes. Furthermore, we observed increased microglial death upon Nrf2 knockdown by the small hairpin RNA approach. Taken together, our study has demonstrated that microglial cells are exquisitely sensitive to MeHg and respond rapidly to MeHg by upregulating the Nrf2-mediated antioxidant response.