Abstract
On November 8th, 2018, the Camp Fire erupted in Northern California's Butte County. It was the deadliest
and most devastating wildfire in California history, with over 153,336 acres burned, 86 confirmed fatalities, over
18,500 structures destroyed including nearly 14,000 residences. Over 50,000 people were evacuated. This fire
was unusual not only in its scale and the rapidity of its spread to urban areas, but also in the vast area
blanketed in smoke that followed for a defined window of two weeks until the first rainfall. The wildfire smoke
plume spread quickly across vast areas of Northern California, and the air quality index was at hazardous
levels for most of Northern California for two weeks, with particulate matter <2.5 µm (PM2.5) concentrations
reaching the highest levels ever recorded in the region, including large metropolitan areas like Sacramento,
Oakland, San Francisco, and San Jose, affecting millions, including ~100,000 pregnant women. There are
widespread concerns about potential health impacts of these urban wildfires and how to mitigate their effects,
especially in vulnerable populations like pregnant women and their developing children. Exposure to extremely
unhealthy levels of wildfire PM2.5 for nearly two weeks for the majority who were unable to leave Northern
California are compounded by the unique composition of urban wildfire smoke. An array of potentially toxic
volatile organic compounds may be released with high temperature combustion of chemicals widely used in
building construction and interior furnishings, such as solvents, glues, metals, formaldehydes, and halogens.
Additionally, like other disasters that act as inherently unpredictable forces of nature that threaten person and
property, wildfires can induce emotional and psychosocial distress and potentially long-term consequences like
persistent post-traumatic stress symptoms and depression. Exposures to contaminants and stress in
combination could have serious long-term developmental consequences if delivered during critical periods in
pregnancy. The goal of this R21 is to rapidly establish a cohort of women who were at different stages of
pregnancy during the Camp Fire and their children, collect biosamples and survey information that will be used
in future studies to determine exposure loads, mechanistic responses, health biomarkers and developmental
outcomes. The cohort will have two eligibility arms: a) those residing within our target area closest to the fire
and within a feasible driving distance for in-person pregnancy, delivery, and postnatal visits and future follow-
up and b) women in Northern California pregnant during the Camp Fire who will complete an online survey and
mail in biospecimens. Participant near-surface wildfire PM2.5 exposure estimated from satellite and ground
monitor data, potential exposure-reducing behaviors, and residence aspects will be examined in relation to
maternal symptoms, stress biomarkers, and child gestational age and birthweight. The cohort and
biorepository established through this proposal will support future studies to understand and minimize the
developmental effects of future wildfires, as they increase in number, duration, and intensity.