This layer displays the percentage and total population with Limited Food Access across the US. A population is defined as having limited food access if they are living more than 1 mile from a supermarket or large grocery store if in an urban area, or more than 10 miles from a supermarket or large grocery store if in a rural area.
Food Desert Census Tracts, Change 2015-2019
This layer displays the change in census tracts labeled as Food Deserts from 2015 to 2019. The Healthy Food Financing Initiative (HFFI) Working Group considers a food desert as a low-income census tract where a substantial number or share of residents has low access to a supermarket or large grocery store.
Food Desert Census Tracts, 2019
This layer displays the location of Food Deserts across the United States based on conditions in 2015. The Healthy Food Financing Initiative (HFFI) Working Group considers a food desert as a low-income census tract where a substantial number or share of residents has low access to a supermarket or large grocery store.
EJ Screen Diesel Particulate Matter
The Diesel PM indicator is the estimated concentration of Diesel PM as provided by the 2017 Air Toxics
update. The value of the indicator is in µg /m3
, and reported at the Census tract level. Block group level
values are assigned by repeating each parent tract level value.
EJ Screen PM 2.5
The PM 2.5 indicator is a measure of potential exposure to inhalable particles that are 2.5 micrometers or smaller. This is measured in terms of annual average concentration in air measured in micrograms per cubic meter. PM 2.5 information included in EJScreen highlights areas across the U.S. that are not meeting the national ambient air quality standard for PM 2.5. In other words, the levels of PM 2.5 present in these areas are deemed harmful to human health. The PM 2.5 indicator in EJScreen is a measure of potential exposure but not a measure of risk. The raw PM 2.5 data is compiled by census tract which is supplied for use in the tool by EPA’s OAQPS. For air toxics risk measures (as opposed to exposure) users can turn to EJScreen’s other three indicators: cancer risk, respiratory HI, and diesel PM.
EJ Screen Air Toxic Cancer Risk
The air toxics cancer risk indicator is the estimated lifetime inhalation cancer risk from the analyzed
carcinogens in ambient outdoor air, as provided by the 2017 Air Toxics data Update. The value of the
indicator is persons per million lifetime. The data is reported at the Census tract level. Block group level
values are assigned by repeating each parent tract level value.
EJ Screen Lead Paint Exposure
The lead paint indicator is the percentage of occupied housing units built before 1960, calculated from
the U.S. Census Bureau’s ACS 5-year summary estimates on age of housing stock. EJScreen uses age of
housing stock as a surrogate for potential lead exposure as regulations banning lead-based residential
paint in 1978 led to the reduction and finally an end to the use of such paint in housing. The percentage
of older housing units is a proxy for potential exposure to lead paint and lead-containing dust that
accumulates indoors, in homes, or in other buildings where lead paint was used. EJScreen uses housing
units built before 1960.
EJ Screen Air Toxic Respiratory Risk
The air toxics respiratory HI indicator is the respiratory HI from the analyzed carcinogens in ambient
outdoor air, as provided by the 2017 Air Toxics Data Update. The data is reported at the Census tract
level. Block group level values are assigned by repeating each parent tract level value.
EJ Screen Superfund Proximity
The Superfund proximity indicator is reflective of the total count of sites proposed and listed (final) on
the National Priorities List (NPL) in each block group within 5 km of the average resident in a block
group, divided by distance, calculated as the population-weighted average of blocks in each block group.
EJ Screen Hazardous Waste Proximity
The hazardous waste proximity indicator is reflective of the total count of hazardous waste facilities in
each block group within 5 km of the average resident in a block group, divided by distance, calculated as
the population-weighted average of blocks in each block group. Hazardous waste facilities are defined as
Resource Conservation and Recovery Act (RCRA) handlers that are either operating TSDFs from RCRA or
reporting LQGs from the 2019 BR.