> For the complete documentation index, see [llms.txt](https://docs.dataplex-consulting.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.dataplex-consulting.com/data-catalog/cdc-open-data-product/cdc-national-center-for-environmental-health.md). # National Center for Environmental Health National Center For Environmental Health datasets in the CDC Open Data Catalog This page contains all datasets in the **National Center For Environmental Health** category of the CDC Open Data Catalog. **Total Datasets in Category**: 5 **Last Updated**: 9/20/2026 #### Daily Grouped Pollen Concentrations (Trees and Weeds) for Select United States Cities, 2003-2024 * **Description**: The National Allergy Bureau™ (NAB™) commonly provides grouped pollen levels. In this dataset, grouped trees and grouped weeds are provided as daily pollen levels and concentrations using data from the NAB. Grouped grass pollen metrics were excluded from selected products to align with data-sharing policies. Public release of grouped grass data could allow inference of taxa-specific concentrations in some contexts; therefore, these metrics are not included. Pollen concentrations are reported as pollen grains per cubic meter (PPCM). Daily pollen levels are determined from PPCM concentrations that fall within the following thresholds, which are based on the proportion of days exceeding these PPCM numbers. The pollen levels provided in this dataset correspond to the following grouped pollen concentrations: Grouped Trees Very High: ≥1500 PPCM High: ≥90–1500 PPCM Moderate: ≥15–90 PPCM Low: <15 PPCM Grouped Weeds Very High: ≥500 PPCM High: ≥50–500 PPCM Moderate: ≥10–50 PPCM Low: <10 PPCM Pollen dates were converted to a 365-day-of-year format using 2024 as the reference year for all date calculations, which is the last year of pollen data for this release. This dataset is part of a series of pollen datasets from the NAB, processed and standardized by the Division of Environmental Health Science and Practice (DEHSP), National Center for Environmental Health (NCEH), CDC. Further details about the pollen data, including collection, counting, and calculations, can be found here: * **Snowflake Schema**: dwv\_nceh\_data * **Databricks Schema**: cdc\_dwv\_nceh\_data * **Table Name**: ere\_is\_the\_clean\_identifier\_daily\_group\_\_435k\_2whj * **Dataset ID**: 435k-2whj * **Category**: National Center for Environmental Health * **Total Rows**: 1,360,662 * **Last Refresh**: 9/19/2026 * **Total Batches**: 3 * **Tags**: environmental health, weed pollen, tree pollen, seasonal allergies, respiratory health, pollen count, pollen concentrations, pollen, high pollen days, hayfever, asthma triggers, allergy season, allergy, allergic rhinitis, allergen exposure, air quality, aeroallergens * **Source Data**: #### Environmental Antecedents of Foodborne Illness Outbreaks * **Description**: Foodborne outbreak investigations often provide data for public health officials to determine how the environment contributed to the outbreak and on how to prevent future outbreaks. State and local health departments are responsible for investigating foodborne illness outbreaks in their jurisdictions and reporting the data to national-level surveillance systems, including information from the environmental assessment. This assessment is designed to describe how the environment contributed to the outbreak and identifies factors that contributed to the outbreak and environmental antecedents to the outbreak. Environmental antecedents, also referred to as root causes, are specific reasons that allow biological or chemical agents to contaminate, survive, or grow in food. From 2017 – 2019, 24 jurisdictions reported 1,430 antecedents from 393 outbreaks to the National Environmental Assessments Reporting System. The most reported antecedents were lack of oversight of employees/enforcement of policies (89.1%), lack of training of employees on specific processes (74.0%), and lack of a food safety culture/attitude towards food safety (57.5%). These findings highlight the critical role that employees play in restaurant food safety and are heavily influenced by restaurant management, who can exercise active managerial control to manage these antecedents. Identifying antecedents during investigations is essential for understanding the outbreak’s root cause and implementing sustainable corrective actions to stop the immediate outbreak and future outbreaks. * **Snowflake Schema**: dwv\_nceh\_data * **Databricks Schema**: cdc\_dwv\_nceh\_data * **Table Name**: environmental\_antecedents\_foodborne\_ill\_\_4khb\_4xch * **Dataset ID**: 4khb-4xch * **Category**: National Center for Environmental Health * **Total Rows**: 1,078 * **Last Refresh**: 9/9/2026 * **Total Batches**: 2 * **Tags**: centers for disease control and prevention, outbreak, foodborne, environmental health * **Source Data**: #### Historical Averages of Pollen Season Timing and Concentrations for Select United States Cities, 2003-2024 * **Description**: The National Allergy Bureau™ (NAB™) commonly provides grouped pollen levels rather than taxa-specific data. In this dataset, however, pollen data are provided as historical averages of pollen season timing and concentrations using data from the NAB. This is the first time pollen data at this level of detail has been made publicly available. Grass pollen metrics were excluded from selected products to align with NAB and CDC data-sharing policies. Pollen concentrations are reported as pollen grains per cubic meter (PPCM) and provided for each year of data available. The pollen data are available from 2003 through 2024 and includes ready-to-use pollen measures including: main pollen season (MPS) start date, peak date, end date, season length, total seasonal pollen concentration (i.e., seasonal pollen integral), average seasonal pollen concentration, peak concentration, and the number of pollen observations per year. Data availability varies by year and pollen type for each NAB site. This dataset is part of a series of pollen datasets from the NAB, processed and standardized by the Division of Environmental Health Science and Practice (DEHSP), National Center for Environmental Health (NCEH), CDC. Further details about the pollen data, including collection, counting, and calculations, can be found here: * **Snowflake Schema**: dwv\_nceh\_data * **Databricks Schema**: cdc\_dwv\_nceh\_data * **Table Name**: ere\_is\_the\_clean\_identifier\_historical\_\_\_7xz4\_qgju * **Dataset ID**: 7xz4-qgju * **Category**: National Center for Environmental Health * **Total Rows**: 1,388 * **Last Refresh**: 9/19/2026 * **Total Batches**: 2 * **Tags**: pollen concentrations, pollen, high pollen days, hayfever, environmental health, asthma triggers, allergy season, allergy, allergic rhinitis, allergen exposure, aeroallergens, air quality, weed pollen, tree pollen, seasonal allergies, respiratory health, pollen count * **Source Data**: #### Weekly Grouped Pollen Concentrations (Trees and Weeds) for Select United States Cities, 2003-2024 * **Description**: The National Allergy Bureau™ (NAB™) commonly provides grouped pollen levels. In this dataset, grouped trees and grouped weeds are provided as weekly pollen concentrations using data from the NAB. Grouped grass pollen metrics were excluded from selected products to align with data-sharing policies. Public release of grouped grass data could allow inference of taxa-specific concentrations in some contexts; therefore, these metrics are not included. Pollen concentrations are reported as pollen grains per cubic meter (PPCM) and provided for each calendar week. This dataset is part of a series of pollen datasets from the NAB, processed and standardized by the Division of Environmental Health Science and Practice (DEHSP), National Center for Environmental Health (NCEH), CDC. Further details about the pollen data, including collection, counting, and calculations, can be found here: * **Snowflake Schema**: dwv\_nceh\_data * **Databricks Schema**: cdc\_dwv\_nceh\_data * **Table Name**: ere\_is\_the\_clean\_identifier\_weekly\_grou\_\_bgxp\_nxmn * **Dataset ID**: bgxp-nxmn * **Category**: National Center for Environmental Health * **Total Rows**: 213,104 * **Last Refresh**: 9/19/2026 * **Total Batches**: 2 * **Tags**: tree pollen, weed pollen, seasonal allergies, respiratory health, pollen count, pollen concentrations, pollen, high pollen days, hayfever, environmental health, asthma triggers, allergy season, allergy, allergic rhinitis, allergen exposure, air quality, aeroallergens * **Source Data**: #### Yearly Pollen Season Timing and Concentrations for Select United States Cities, 2003-2024 * **Description**: The National Allergy Bureau™ (NAB™) commonly provides grouped pollen levels rather than taxa-specific data. In this dataset, however, pollen data are provided as yearly pollen season timing and concentrations using data from the NAB. This is the first time pollen data at this level of detail has been made publicly available. Grass pollen metrics were excluded from selected products to align with NAB and CDC data-sharing policies. Pollen concentrations are reported as pollen grains per cubic meter (PPCM) and provided for each year of data available. The pollen data are available from 2003 through 2024 and includes ready-to-use pollen measures including: main pollen season (MPS) start date, peak date, end date, season length, total seasonal pollen concentration (i.e., seasonal pollen integral), average seasonal pollen concentration, peak concentration, and the number of pollen observations per year. Data availability varies by year and pollen type for each NAB site. This dataset is part of a series of pollen datasets from the NAB, processed and standardized by the Division of Environmental Health Science and Practice (DEHSP), National Center for Environmental Health (NCEH), CDC. Further details about the pollen data, including collection, counting, and calculations, can be found here: * **Snowflake Schema**: dwv\_nceh\_data * **Databricks Schema**: cdc\_dwv\_nceh\_data * **Table Name**: ere\_is\_the\_clean\_identifier\_yearly\_taxa\_\_rq2k\_zaqh * **Dataset ID**: rq2k-zaqh * **Category**: National Center for Environmental Health * **Total Rows**: 18,558 * **Last Refresh**: 9/19/2026 * **Total Batches**: 2 * **Tags**: environmental health, weed pollen, tree pollen, seasonal allergies, respiratory health, pollen count, pollen concentrations, pollen, high pollen days, hayfever, asthma triggers, allergy season, allergy, allergic rhinitis, allergen exposure, air quality, aeroallergens * **Source Data**: --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. 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