Wildfire smoke exposure during pregnancy and perinatal, obstetric, and early childhood health outcomes: A systematic review and meta-analysis

The Influence of Wildfire Smoke on Ambient PM2.5 Chemical Species Concentrations in the Contiguous US

Wildfires significantly contribute to ambient air pollution, yet our understanding of how wildfire smoke influences specific chemicals and their resulting concentration in smoke remains incomplete. We combine 15 years of daily species-specific PM2.5 concentrations from 700 air pollution monitors with satellite-derived ambient wildfire smoke PM2.5, and use a panel regression to estimate wildfire smoke's contribution to the concentrations of 27 different chemical species in PM2.5. Wildfire smoke drives detectable increases in the concentration of 25 out of the 27 species with the largest increases observed for organic carbon, elemental carbon, and potassium. We find that smoke originating from wildfires that burned structures had higher concentrations of copper, lead, zinc, and nickel relative to smoke from fires that did not burn structures. Wildfire smoke is responsible for an increasing share of ambient concentrations of multiple species, some of which are particularly harmful to health. Using a risk assessment approach, we find that wildfire-induced enhancement of carcinogenic species concentrations could cause increases in population cancer risk, but these increases are very small relative to other environmental risks. We demonstrate how combining ground-monitored and satellite-derived data can be used to measure wildfire smoke's influence on chemical concentrations and estimate population exposures at large scales.

Approaches in landscape fire smoke pregnancy research and the impact on offspring: A review of knowledge gaps and recommendations

The increase in wildfires and bushfires due to climate change means that more people, including pregnant women and their fetuses will be exposed to landscape fire smoke. Although there is evidence to suggest that pregnancy landscape fire exposure is associated with lower birth weight, preterm birth and pregnancy loss, there is a lack of information on many other perinatal outcomes, as well as information on subsequent respiratory outcomes in children. Furthermore, due to the generally short term (hours/days) and intermittent nature of landscape fire smoke exposure, the knowledge to date has largely relied on natural experiments and ecological studies which can be subject to misclassification of exposure and a lack of precision. On the other hand, general urban outdoor air pollution exposure during pregnancy and subsequent perinatal and respiratory effects has been well studied. In particular, as air exposure modelling has improved so have the adaptations of methods to analyze the effects of air pollution exposure during pregnancy enabling critical windows of exposure to be identified. In this narrative review we summarize the current state of knowledge about the perinatal and respiratory effects of pregnancy landscape fire and particulate matter <2.5 μm in diameter (PM2.5) air pollution exposure, including a comment on analysis methods to date, and an assessment of how methodologies used in general air pollution research in relation to pregnancy exposure can be further harnessed for landscape fire smoke exposure pregnancy research.

Strengthening Maternal and Infant Health Resilience Before Weather and Climate Disasters: Preparedness Resources from CDC's Division of Reproductive Health

This report describes opportunities to address emergency preparedness to incorporate the needs of pregnant and postpartum populations. This report briefly summarizes data on the impacts of weather and climate disasters on maternal and infant health and outlines opportunities for individuals, health care providers, and public health practitioners to increase capacity to prepare for these occurrences, which are becoming more frequent and costly. Specific resources from the U.S. Centers for Disease Control and Prevention's Division of Reproductive Health are shared to support individual preparedness, communication of disaster safety messages, and emergency preparedness planning capacity among health care providers and health departments.

A scoping review of wildfire smoke risk communications: issues, gaps, and recommendations

BACKGROUND

Wildfire smoke exposure has become a growing public health concern, as megafires and fires at the wildland urban interface increase in incidence and severity. Smoke contains many pollutants that negatively impact health and is linked to a number of health complications and chronic diseases. Communicating effectively with the public, especially at-risk populations, to reduce their exposure to this environmental pollutant has become a public health priority. Although wildfire smoke risk communication research has also increased in the past decade, best practice guidance is limited, and most health communications do not adhere to health literacy principles: readability, accessibility, and actionability. This scoping review identifies peer-reviewed studies about wildfire smoke risk communications to identify gaps in research and evaluation of communications and programs that seek to educate the public.

METHODS

Four hundred fifty-one articles were identified from Web of Science and PubMed databases. After screening, 21 articles were included in the final sample for the abstraction process and qualitative thematic analysis. Ten articles were based in the US, with the other half in Australia, Canada, Italy, and other countries. Fifteen articles examined communication materials and messaging recommendations. Eight papers described communication delivery strategies. Eleven articles discussed behavior change. Six articles touched on risk communications for vulnerable populations; findings were limited and called for increasing awareness and prioritizing risk communications for at-risk populations.

RESULTS

This scoping review found limited studies describing behavior change to reduce wildfire smoke exposure, characteristics of effective communication materials and messaging, and communication delivery strategies. Literature on risk communications, dissemination, and behavior change for vulnerable populations was even more limited.

CONCLUSIONS

Recommendations include providing risk communications that are easy-to-understand and adapted to specific needs of at-risk groups. Communications should provide a limited number of messages that include specific actions for avoiding smoke exposure. Effective communications should use mixed media formats and a wide variety of dissemination strategies. There is a pressing need for more intervention research and effectiveness evaluation of risk communications about wildfire smoke exposure, and more development and dissemination of risk communications for both the general public and vulnerable populations.