Air quality: standard: hydrogen sulfide.
SB 58
California Bills
20250SB__005895AMD INTRODUCED 2025-01-08 AMENDED_SENATE 2025-03-04 AMENDED_SENATE 2026-01-05 AMENDED_SENATE 2026-01-14 AMENDED_ASSEMBLY 2026-06-15 REVISED 2026-06-23 2025 SB AMD Introduced by Senator Padilla (Coauthor: Senator Blakespear) (Coauthors: Assembly Members Alvarez, Boerner, and Ward) LEAD_AUTHOR SENATE Padilla COAUTHOR SENATE Blakespear COAUTHOR ASSEMBLY Alvarez COAUTHOR ASSEMBLY Boerner COAUTHOR ASSEMBLY Ward
An act to add
Section 41514.7 to the Health and Safety Code, relating to air pollution. air pollution Air quality: standard: hydrogen sulfide. Existing law generally designates the State Air Resources Board as the state agency with the primary responsibility for the control of vehicular air pollution, and designates air pollution control districts and air quality management districts with the primary responsibility for the control of air pollution from all sources other than vehicular sources.
Existing law requires the state board to inventory sources of air pollution within the air basins of the state, determine the kinds and quantity of air pollutants, and monitor air pollutants in cooperation with districts and other agencies. Existing law requires the state board to adopt standards of ambient air quality for each air basin in consideration of the public health, safety, and welfare, including, but not limited to, health, illness, irritation to the senses, aesthetic value, interference with visibility, and effects on the economy.
Existing law authorizes these standards to vary from one air basin to another. This bill would require the state board, in consultation with specified entities, to develop, as provided, a response framework that establishes best practices and guidance for addressing fugitive and natural sources of hydrogen sulfide gas and for community preparation and response to hydrogen sulfide exposure events originating from these sources.
The bill would require the state board, in developing the response framework, to conduct at least public workshops, including at least one located in the Tijuana River Valley region, at least one located in the Salton Sea region, and at least one selected in consultation with a community that has experienced significant hydrogen sulfide exposure. The bill would require the air pollution control districts and air quality management districts to adopt, and would authorize local environmental and public health agencies to consider, any threshold level later developed by the office pursuant to the bill.
By imposing new duties on air pollution control districts and air quality management districts, the bill would impose a state-mandated local program.</xhtml:p><xhtml:p> The bill would also authorize the state board to adopt additional or updated standards based on the threshold levels developed pursuant to the bill.
The bill would additionally express the intent of the Legislature to develop guidelines that would require the state board, in consultation with specified entities, to develop a response framework to establish best practices and guidance based on the office’s development of thresholds established pursuant to the bill.</xhtml:p><xhtml:p>The California Constitution requires the state to reimburse local agencies and school districts for certain costs mandated by the state.
Statutory provisions establish procedures for making that reimbursement.</xhtml:p><xhtml:p>This bill would provide that no reimbursement is required by this act for a specified reason.</xhtml:p>"?> MAJORITY NO YES NO NO NO NO NO NO NO NO The people of the State of California do enact as follows:
SECTION 1. The Legislature finds and declares all of the following: (
a) Hydrogen sulfide is a colorless, highly toxic gas with a strong odor detectable at very low concentrations. (
b) The state board adopted a one-hour ambient air quality standard of 0.03 parts per million (30 parts per billion) for hydrogen sulfide in 1969, primarily to address odor nuisances, rather than chronic or long-term public health effects. (
c) Exposure to hydrogen sulfide is associated with headache, nausea, respiratory irritation, nasal symptoms, and neurological effects, and current evidence indicates that chronic exposure can contribute to persistent respiratory and neurological impacts, with heightened susceptibility among children, older adults, and individuals with preexisting health conditions. (
d) Although the state’s existing hydrogen sulfide standard has not been updated for years and may not consider contemporary health science, cumulative exposure assessments, or community vulnerability, it may also be insufficient in addressing public health impacts near hydrogen sulfide hotspots across the state. (
e) Monitoring data in regions such as the Tijuana River Valley in the County of San Diego and the Salton Sea in the Counties of Imperial and Riverside have shown exceedances of the state hydrogen sulfide standard; however, it is difficult to identify a responsible party that could be subject to plans to attain the standards. (
f) Thus, there is a need for a response framework that can address local needs in response to harmful air quality. (
g) Modern scientific research conducted in the Tijuana River Valley shows that communities near the river experience prolonged and chronic low-level hydrogen sulfide exposures, with concentrations of hydrogen sulfide frequently exhibiting sudden increases above the current state standard in durations of less than one hour. These sudden increases are in
part caused by episodic influxes of transboundary pollution and are not captured in the time-averaged concentrations made to compare to the one-hour standard. (
h) Health symptoms associated with exposure to hydrogen sulfide have been reported in the South Bay region and the cities of San Diego and Imperial Beach, and include respiratory and gastrointestinal issues, headaches, fatigue, nausea, skin irritation, and respiratory irritation. (
i) Monitoring data indicate that hydrogen sulfide concentrations near sensitive locations, including Berry Elementary School in the Tijuana River Valley, have exceeded the current standard, demonstrating that children and other vulnerable populations are exposed to elevated levels. (
j) Similarly, communities surrounding the Salton Sea experience frequent elevated and chronic low-level hydrogen sulfide concentrations, caused by anaerobic biological activity, decomposition of organic matter, and shoreline emissions, with recorded levels frequently exceeding the state standard. (
k) These exposures disproportionately affect vulnerable and environmentally overburdened communities, including low-income households, immigrant communities, Latino and tribal populations, and areas already experiencing elevated rates of respiratory and other health conditions, exacerbating existing health inequities. (
l) The Office of Environmental Health Hazard Assessment indicates that chronic exposure to hydrogen sulfide at levels below the current one-hour standard can adversely affect human health. (
m) Furthermore, factors such as concentration averaging times, local and regional climate, and indoor versus outdoor exposure should be considered in assessing concentration levels and their impacts to public health. (
n) Thus, the Legislature recognizes a need to develop additional threshold levels for hydrogen sulfide that consider these factors in conjunction with local agency response to address public health issues.
SEC.
Section 41514.7 is added to the Health and Safety Code , to read: 41514.7. (
a) For purposes of this section, the following
definitions apply: (1) “Fugitive source” means any source of emissions of hydrogen sulfide gas that is not currently regulated as a stationary source by a local air pollution control district or air quality management district. (1)</xhtml:p>"?> (2) “Local environmental and public health agencies” means any local entity that a health officer, as defined in
Section 120100, serves, or any local environmental health agency. (2)<xhtml:span class="EnSpace"/>“Office” means the Office of Environmental Health Hazard Assessment.</xhtml:p><xhtml:p>(b)<xhtml:span class="EnSpace"/>On or before January 1, 2030, the office shall develop health-based threshold levels for hydrogen sulfide. The threshold levels shall be in addition to any standards adopted pursuant to paragraph (2) of subdivision (
a) of
Section 39606.</xhtml:p><xhtml:p>(c)<xhtml:span class="EnSpace"/>(1)<xhtml:span class="EnSpace"/>In developing the threshold levels pursuant to subdivision (b), the office shall consider, but not be limited to considering, all of the following:</xhtml:p><xhtml:p>(A)<xhtml:span class="EnSpace"/>Current scientific literature regarding acute, subchronic, and chronic health effects of hydrogen sulfide exposure, including the impact of chronic low-level exposure.</xhtml:p><xhtml:p>(B)<xhtml:span class="EnSpace"/>The adequacy of current averaging times for hazardous exposure.
The office shall consider the need for additional threshold levels based on various averaging times, including, but not limited to, 10-minute, 30-minute, 8-hour, 24-hour, or chronic exposure durations.</xhtml:p><xhtml:p>(C)<xhtml:span class="EnSpace"/>Health-related impacts due to outdoor and indoor air exposure.</xhtml:p><xhtml:p>(D)<xhtml:span class="EnSpace"/>Local and regional climates.
The office shall consider whether existing standards and threshold levels are appropriate for specific locations or sites.</xhtml:p><xhtml:p>(E)<xhtml:span class="EnSpace"/>Current federal, state, and international health-based exposure guidelines.</xhtml:p><xhtml:p>(F)<xhtml:span class="EnSpace"/>Corresponding actions for threshold levels, including, but not limited to, public notification and local agency response.</xhtml:p><xhtml:p>(2)<xhtml:span class="EnSpace"/>The office may develop threshold levels for additional air pollutants with the considerations specified in paragraph (1) upon an appropriation for these purposes from the Legislature.</xhtml:p><xhtml:p>(d)<xhtml:span class="EnSpace"/>The office may develop threshold levels pursuant to subdivision (
b) in consultation with the state board, districts, the State Department of Public Health, local or regional authorities, local environmental and public health agencies, universities and academic institutions, affected tribal governments, and community-based organizations.</xhtml:p><xhtml:p>(e)<xhtml:span class="EnSpace"/>In developing the threshold levels pursuant to subdivision (b), the office shall conduct at least three public workshops located in all of the following:</xhtml:p><xhtml:p>(1)<xhtml:span class="EnSpace"/>At least one in the Tijuana River Valley region.</xhtml:p><xhtml:p>(2)<xhtml:span class="EnSpace"/>At least one in the Salton Sea region.</xhtml:p><xhtml:p>(3)<xhtml:span class="EnSpace"/>At least one selected in consultation with a community that has experienced significant hydrogen sulfide exposure.</xhtml:p><xhtml:p>(f)<xhtml:span class="EnSpace"/>The districts shall adopt, and local environmental and public health agencies may consider, any threshold level developed by the office pursuant to subdivision (b).</xhtml:p><xhtml:p>(g)<xhtml:span class="EnSpace"/>Based on the threshold levels developed pursuant to subdivision (b), the state board may adopt additional or updated standards, pursuant to paragraph (2) of subdivision (
a) of
Section 39606.</xhtml:p>"?> (3) “Natural source” means a source of hydrogen sulfide occurring in nature as a result of environmental circumstances. (h)</xhtml:p>"?> (
b) The state board shall, in consultation with the local air pollution control districts and local air quality management districts, the Office of Emergency Services, the State Department of Public Health, regional water quality control boards or other local or regional authorities, local environmental and public health agencies, universities and academic institutions, affected tribal governments, and community-based organizations, develop a response framework that establishes best practices and guidance for addressing fugitive and natural sources of hydrogen sulfide gas and for community preparation and response to hydrogen sulfide exposure events originating from these sources.
The guidelines shall consider cross-media releases, and develop integrated, multiagency approaches to identify and address fugitive and natural sources, and methods for reducing identified fugitive and natural sources of hydrogen sulfide gas in impacted communities. In developing the response framework, the state board shall consider and evaluate the inadequacies of the Acute, 8-hour, and Chronic Reference Exposure Levels for fugitive and natural sources of emissions for developing the response plan. The evaluation shall consider all of the following:
(1) Current scientific literature regarding acute, subchronic, and chronic health effects of hydrogen sulfide exposure, including the impact of chronic low-level exposure.
(2) The adequacy of current averaging times for characterizing hazardous exposure, including the frequency and duration of possible exposures.
(3) The influence of local and regional climates, outdoor, and indoor settings on exposure. (
c) In developing the response framework pursuant to subdivision (b), the state board shall conduct at least three public workshops located in all of the following:
(1) At least one in the Tijuana River Valley region.
(2) At least one in the Salton Sea region.
(3) At least one selected in consultation with a community that has experienced significant hydrogen sulfide exposure. <caml:Num>SEC. 3.</caml:Num><caml:Content><xhtml:p>No reimbursement is required by this act pursuant to
Section of
Article XIII<xhtml:span class="ThinSpace"/>B of the California Constitution because a local agency or school district has the authority to levy service charges, fees, or assessments sufficient to pay for the program or level of service mandated by this act, within the meaning of