Investing In Clean Agriculture: How California Can Strengthen Agriculture, Reduce Pollution And Save Money

Pacific Institute | February 8th, 2005

Global competition, suburban encroachment, tighter regulations, and rising input costs are making farming in California more difficult and, in some cases, less profitable

Global competition, suburban encroachment, tighter regulations, and rising input costs are making farming in California more difficult and, in some cases, less profitable. At the same time, pesticide pollution from farming is causing significant harm to California’s surface and groundwater, air quality, and human health. But there is a way to reduce pesticide use, protect the environment, and help farmers stay competitive according to a new report, Investing In Clean Agriculture: How California Can Strengthen Agriculture, Reduce Pollution And Save Money, published today by the Pacific Institute. “Business as usual isn’t working for our state,” declared Dr. Gary H. Wolff, author of the report and Principal Economist and Engineer with the Pacific Institute of Oakland, California. “Our plan will reduce pesticide use, protect public health, preserve the environment, and help California’s farmers stay competitive in a rapidly changing economy. We think this will be a win for consumers, a win for taxpayers, and a win for agriculture.” A US Geological Survey study of groundwater wells in the San Joaquin-Tulare Basin found at least one pesticide in 59 of 100 samples. But current efforts to reduce pesticide pollution are caught up in the courts. The rebate approach creates a voluntary incentive to reduce pesticide use while leaving it up to farmers to figure out the best way forward. “The Pacific Institute’s innovative proposal will reward farmers who are willing to learn about farming practices that protect water quality,” noted Leland Swenson of the Community Alliance With Family Farmers. “It is a voluntary and incentive-based way for farmers to respond to water quality regulations and keep pesticides out of drinking water.” The report describes how farmers can be rewarded for learning voluntarily about sustainable agricultural practices. A modest increase in the statewide “mill” fee, now levied on pesticides, is returned to farmers who take a short course on sustainable agriculture techniques and storm runoff management. This helps farmers stay competitive while reducing pesticide use – which will protect human health, preserve the environment, and eventually save taxpayers money by reducing medical costs. “Everybody wins if we can reduce our dependence on pesticides,” said Jonathan Kaplan of NRDC. “As the head of California’s Department of Pesticide Regulation just stated, ‘Integrated Pest Management is good for our economy as well as our environment’.” Investing In Clean Agriculture: How California Can Strengthen Agriculture, Reduce Pollution And Save Money estimates that the voluntary program and fee increase could bring $60 million per year into the agricultural sector while also bringing the most cutting edge research on sustainable farming techniques to those in the field.

Is there an urban pesticide signature? Urban streams in five U.S. regions share common dissolved-phase pesticides but differ in predicted aquatic toxicity

Science of the Total Environment (Elsevier) | June 15th, 2021

Pesticides occur in urban streams globally, but the relation of occurrence to urbanization can be obscured by regional differences. In studies of five regions of the Unit

Pesticides occur in urban streams globally, but the relation of occurrence to urbanization can be obscured by regional differences. In studies of five regions of the United States, we investigated the effect of region and urbanization on the occurrence and potential toxicity of dissolved pesticide mixtures. We analyzed 225 pesticide compounds in weekly discrete water samples collected during 6–12 weeks from 271 wadable streams; development in these basins ranged from undeveloped to highly urbanized. Sixteen pesticides were consistently detected in 16 urban centers across the five regions—we propose that these pesticides comprise a suite of urban signature pesticides (USP) that are all common in small U.S. urban streams. These USPs accounted for the majority of summed maximum pesticide concentrations at urban sites within each urban center. USP concentrations, mixture complexity, and potential toxicity increased with the degree of urbanization in the basin. Basin urbanization explained the most variability in multivariate distance-based models of pesticide profiles, with region always secondary in importance. The USPs accounted for 83% of pesticides in the 20 most frequently occurring 2-compound unique mixtures at urban sites, with carbendazim+prometon the most common. Although USPs were consistently detected in all regions, detection frequencies and concentrations varied by region, conferring differences in potential aquatic toxicity. Potential toxicity was highest for invertebrates (benchmarks exceeded in 51% of urban streams), due most often to the neonicotinoid insecticideimidacloprid and secondarily to organophosphate insecticides and fipronil. Benchmarks were rarely exceeded in urban streams for plants (at 3% of sites) or fish (<1%). We propose that the USPs identified here would make logical core (nonexclusive) constituents for monitoring dissolved pesticides in U.S. urban streams, and that unique mixtures containing imidacloprid, fipronil, and carbendazim are priority candidates for mixtures toxicity testing.

Land Use, Pollutants, and Water Quality in California Streams

California State Water Resources Control Board (SWRCB) | April 12th, 2012

A number of spatial patterns were evident in this survey of watersheds from throughout California. Stream sediment concentrations of heavy metals, such as cadmi

A number of spatial patterns were evident in this survey of watersheds from throughout California. Stream sediment concentrations of heavy metals, such as cadmium, copper, lead and zinc, tended to be highest in urbanized Los Angeles and San Francisco Bay area watersheds. Metal concentrations in sediments from San Leandro Creek (SF Bay area), Ballona Creek and San Gabriel River (Los Angeles area) were among the highest in the state. These metals are released to the environment from brake pads, plumbing, industrial and commercial activities. Industrial organic compounds such as PCBs (banned since the 1970s), PBDEs (flame retardants) and PAHs (hydrocarbons) were also generally highest in stream sediments from the Los Angeles and San Francisco Bay areas, though high concentrations were also measured in some more remote locations. In contrast to this urban pattern, mercury concentrations were highest in sediments from watersheds where it is geologically abundant and historically mined, though some urban streams also had relatively high mercury levels. The persistent legacy pesticide DDT was found in stream sediments from most urban and agricultural watersheds, where recent soil disturbance from development and tillage likely mobilizes DDT residues from applications more than 40 years ago. Pyrethroid pesticides are increasing in use in California and were detected in 55% of the samples statewide (51 of 92). The highest pyrethroid concentrations were measured in sediments collected from urban watersheds, plus two agricultural watersheds along the central coast. Approximately one quarter of the sediment samples collected were significantly toxic to amphipods, which are resident crustaceans representative of important aquatic food web links. Of these samples, 6.5% were identified as highly toxic. The highly toxic samples were collected from agricultural watersheds in the Tulare basin and central coast, in urban areas of southern California, and in the Tijuana River. Other toxic samples were collected from a wide range of watershed types, including those along the north coast, the Tahoe area, and urban and agricultural areas across the state. On a statewide basis, watersheds with greater than 10% urban land cover had consistently higher sediment pollutant concentrations and toxicity than did watersheds characterized by agricultural or other land cover types. Metals, industrial compounds, DDTs, and pyrethroid pesticides were all found at significantly higher concentrations in urban streams. This pattern is evident at the statewide level, but other local and regional studies have previously shown that pollution levels and toxicity can be strongly related to agricultural and other land uses in specific areas. This is because the “agricultural” land use category used in the SPoT analysis is comprised of many different types of crops and farming practices, and the amount of polluted runoff from these lands varies depending on the types of practices employed.

Long-term Monitoring of Pollutants in Fish and Mussels Documents Major Improvements and Persistent Problems

California State Water Resources Control Board (SWRCB) | December 1st, 2007

Of the 390 sites sampled between 1998 and 2003, 32 percent fell into the “low” contamination category. These sites were scattered throughout the state, with

Of the 390 sites sampled between 1998 and 2003, 32 percent fell into the “low” contamination category. These sites were scattered throughout the state, with a particular prevalence in the Sierra Nevada and the area north of San Diego. Unfortunately, the Delta region had relatively few sites with low concentration of pollutants. In general, PCB and DDT levels in fish and mussels across California have declined greatly since the 1970s, and many species have bounced back in response to the decline in DDT levels. However, the report also found that present concentrations of pollutants in fish collected from many California water bodies are high enough to cause concern for possible effects on human health and to have a significant impact on the fishing beneficial use. The report found that fish in 68 percent of the water bodies sampled have “moderate to very high levels of mercury or persistent organics (such as PCBs and organochlorinated pesticides like DDT).” Consumption advisories exist for only a fraction of the water bodies likely to need them. Many water bodies with elevated contaminant levels in fish are near population centers and are popular for fishing. Furthermore, subsistence fishing is increasing, and consumption of contaminated fish is an environmental justice issue.

Methods of Analysis—Determination of Pesticides in Filtered Water and Suspended Sediment using Liquid Chromatography- and Gas Chromatography-Tandem Mass Spectrometry

U.S. Geological Survey (USGS) | January 31st, 2024

The widespread application of pesticides in agricultural and urban areas leads to their presence in surface waters. Presence of these biologically active chemicals in en

The widespread application of pesticides in agricultural and urban areas leads to their presence in surface waters. Presence of these biologically active chemicals in environmental waters potentially has adverse effects on nontarget organisms. To better understand the environmental fate of these contaminants, a robust method to capture chemicals with wide-ranging physicochemical properties has been developed. The method was developed by the U.S. Geological Survey’s Organic Chemistry Research Laboratory to monitor pesticides, pesticide degradates, and other agrochemicals in environmental surface waters throughout the country. The analysis involves a multiresidue method to determine 183 pesticides and pesticide degradates in filtered water samples and 178 pesticides and pesticide degradates in paired suspended sediment samples. After the filtration of whole water, contaminants are individually measured in the filtered water and the collected suspended sediment. Filtered water is extracted via solid-phase extraction, whereas suspended sediment is extracted using an ultrasonication, solid-liquid extraction. Samples are analyzed by liquid chromatography-tandem mass spectrometry using an electrospray ionization source in positive and negative modes and analyzed by gas chromatography-tandem mass spectrometry using an advanced electron ionization source in positive mode. Instrument parameters were optimized for the highest sensitivity, and at least two transitions (quantifier and qualifier) were monitored for each analyte. Recoveries in test filtered water (n=9; 183 analytes) from the American River, California, and suspended sediment (n=9; 178 analytes) samples fortified at 15 nanograms per liter (ng/L) ranged from 70.1 to 121.0 and 71.1 to 117.0 percent in water and suspended sediment filter samples, respectively.

Multiple lines of evidence point to pesticides as stressors affecting invertebrate communities in small streams in five United States regions

Science of the Total Environment (Elsevier) | February 2nd, 2024

Multiple lines of evidence point to pesticides as stressors affecting invertebrate communities in small streams in five United States regions

Science of the Total Environment (Elsevier) | January 24th, 2024

Neonicotinoids and their Degradates in San Francisco Bay Water

San Francisco Estuary Institute (SFEI) | July 1st, 2020

The Regional Monitoring Program for Water Quality in San Francisco Bay (RMP) screened Bay waters for neonicotinoid pesticides, comparing levels to toxicity thresholds to

The Regional Monitoring Program for Water Quality in San Francisco Bay (RMP) screened Bay waters for neonicotinoid pesticides, comparing levels to toxicity thresholds to inform placement of this class of emerging contaminants within the tiered risk-based framework. Neonicotinoids are one of the most widely used classes of insecticides in the world. Given their widespread use in agricultural and urban environments, and ubiquitous detections in surface waters, there is growing concern about consequences for non-target species such as aquatic invertebrates, insects, birds, and fish. In the summer of 2017, open Bay water samples were collected during the RMP Status and Trends Water Cruise. Samples were analyzed for 19 neonicotinoids and metabolites. The only neonicotinoid detected was imidacloprid, an active ingredient used in both urban and agricultural applications. Imidacloprid was detected at a single site above the method detection limits (2.2-2.6 ng/L) in Lower South Bay at a level of 4.2 ng/L. This value is within the range of concentrations found in a separate RMP study in water samples collected from the South and Lower South Bay margins in 2017. Imidacloprid was detected at 3 of 12 of the margin sites at levels between 3.9 and 11 ng/L; no other neonicotinoids were detected. Of note, these RMP studies appear to represent the first evaluation of ambient neonicotinoid concentrations in an estuarine environment in the nation. Two significant pathways of imidacloprid contamination to the Bay are treated wastewater and runoff from the surrounding, primarily urban landscape. Previous RMP monitoring of wastewater influent and effluent, consisting of 24-hour composite samples collected from eight wastewater treatment facilities in the Bay Area in September 2015, detected imidacloprid in 100% of samples at levels up to 310 ng/L. Independent surveys in both northern and southern California urban areas confirm that imidacloprid is a commonly detected insecticide in urban runoff. For example, a San Francisco Bay Area study in Fairfield and Suisun City detected imidacloprid at up to 1,462 ng/L in urban creek waters. However, these concentrations diminished to below detection limits in downstream samples as creek waters mixed with brackish waters from the Bay. While Bay Area agricultural runoff has not been well-characterized with respect to imidacloprid, this pathway may also be of potential interest. A hydrodynamic dilution spreadsheet model was applied as an additional screening tool to explore predicted spatial patterns and temporal trends in imidacloprid concentrations in Bay subembayments. Model inputs were based on available data on concentrations in wastewater effluent and runoff. The model predicted that Lower South Bay levels of imidacloprid would be higher than in other subembayments. The Lower South Bay was also the only subembayment where imidacloprid concentrations were consistently predicted to be higher than method detection limits. The model indicated that wastewater was a dominant pathway for imidacloprid. However, stormwater discharges during the wet season could potentially lead to higher levels in the Bay, suggesting that dry season monitoring may not fully capture maximum concentrations. The results of this simplified dilution model are based on limited input data and do not include all relevant processes and removal mechanisms; they should be interpreted with caution and best viewed as a first step toward quantifiable prediction of open Bay concentrations. Open Bay and margins monitoring of imidacloprid revealed that detected concentrations in Lower South Bay were comparable to or greater than protective US and European Union thresholds that range from 4.8 to 10 ng/L. These observations, in combination with widespread and increasing use of this pesticide in urban settings, indicate that this contaminant should be classified as a Moderate Concern in the RMP tiered risk-based framework for contaminants of emerging concern. Other neonicotinoid pesticides and degradates should be classified as Possible Concern, given their more limited availability in urban use pesticide products, as well as additional uncertainties, particularly the lack of chronic toxicity data and potential for cumulative impacts to wildlife. Additional monitoring is not recommended at this time, due to existing monitoring in urban streams conducted primarily by the California Department of Pesticide Regulation (CDPR). In the future, it may be appropriate for the RMP to explore opportunities for wet season monitoring in Bay water, or in urban runoff. Considering the low toxicity thresholds of these compounds (i.e., in the low ng/L range), analytical methods employed should be improved to provide method detection limits well below toxicity thresholds.

New-generation pesticides are prevalent in California's Central Coast streams

Science of the Total Environment (Elsevier) | October 7th, 2021

Pesticides are widely recognized as important biological stressors in streams, especially in heavily developed urban and agricultural areas like the Central California Co

Pesticides are widely recognized as important biological stressors in streams, especially in heavily developed urban and agricultural areas like the Central California Coast region. We assessed occurrence and potential toxicity of pesticides in small streams in the region using two analytical methods: a broad-spectrum (223 compounds) method in use since 2012 and a newly developed method for 30 additional new-generation fungicides and insecticides. At least one pesticide compound was identified in 83 of the 85 streams sampled. About one-half (48%) of the 253 pesticides measured were detected at least once and 27 were detected in 10% or more of samples. Three of the top 4, and 6 of the top 10 most frequently detected compounds (chlorantraniliprole, dinotefuran, boscalid, thiamethoxam, clothianidin and the fluopicolide degradate 2,6-dichlorobenzamide) were analyzed by the new method. Pesticide mixtures were common, with two or more pesticide compounds detected in 81% of samples and 10 or more in 32% of samples. The pesticide count at a site was relatively consistent over the 6-week study. Four sites with mixed land-use in the lower basin (

Occurrence and Sources of Pesticides to Urban Wastewater and the Environment

American Chemical Society (ACS) | March 26th, 2019

Municipal wastewater has not been extensively examined as a pathway by which pesticides contaminate surface water, particularly relative to the well-recognized pathways o

Municipal wastewater has not been extensively examined as a pathway by which pesticides contaminate surface water, particularly relative to the well-recognized pathways of agricultural and urban runoff. A state-of-the-science review of the occurrence and fate of current-use pesticides in wastewater, both before and after treatment, indicates this pathway is significant and should not be overlooked. A comprehensive conceptual model is presented to establish all relevant pesticide-use patterns with the potential for both direct and indirect down-the-drain transport. Review of available studies from the United States indicates 42 pesticides in current use. While pesticides and pesticide degradates have been identified in wastewater, many more have never been examined in this matrix. Conventional wastewater treatment technologies are generally ineffective at removing pesticides from wastewater, with high removal efficiency only observed in the case of highly hydrophobic compounds, such as pyrethroids. Aquatic life reference values can be exceeded in undiluted effluents. For example, seven compounds, including three pyrethroids, carbaryl, fipronil and its sulfone degradate, and imidacloprid, were detected in treated wastewater effluent at levels exceeding U.S. Environmental Protection Agency (US EPA) aquatic life benchmarks for chronic exposure to invertebrates. Pesticides passing through wastewater treatment plants (WWTPs) merit prioritization for additional study to identify sources and appropriate pollution-prevention strategies. Two case studies, diazinon and chlorpyrifos in household pesticide products, and fipronil and imidacloprid in pet flea control products, highlight the importance of identifying neglected sources of environmental contamination via the wastewater pathway. Additional monitoring and modeling studies are needed to inform source control and prevention of undesirable alternative solutions.