Laboratory Services
Chemistry & Radiochemistry Section
Esala Chandrasenaā, Section Chief
Dr. Syrago-Styliani Petropoulou, Unit Supervisor
The DWRLB Chemistry Unit (CU) provides a wide range of testing services for inorganic and organic contaminants in drinking water and drinking water sources. This includes regulated toxic metals (e.g., arsenic, lead, cadmium) determined by sensitive analytical techniques such as Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). ICP-MS is also increasingly used to determine unregulated metals and for quantitation of long-lived radionuclides. CU also determines anions by Ion Chromatography (IC) and Ion Chromatography coupled to Electrospray (ESI) MS and ESI tandem MS. These anions include: common anions (fluoride, chloride, sulfate, nitrate, nitrite, phosphate); disinfection by-products (bromate, chlorite, chlorate); and miscellaneous anions (perchlorate, chromate, hexavalent chromium). General water quality parameters are determined by ion-selective electrode, spectroĀphotoĀmetry, distillation, amperometry, and titration techniques.
DWRLB relies on instrumental analysis to analyze many organic contaminants including gas chromatography, liquid chromatography, and mass spectrometry methods in a variety for forms (e.g. purge & trap GC-MS). Organic contaminant testing includes analyses for federally-regulated and California-only regulated contaminants in drinking water.
CU is certified by The NELAC Institute (TNIā) for testing chemicals in drinking water and belongs to US EPAās Environmental Response Laboratory Network (ERLN) as well as the Water Laboratory Alliance (WLA). Current research interests include developing, validating new test methods for low level detection of contaminants of emerging concern in public health such as the persistent perfluorinated chemicals (PFAS), pharmaceuticals, nitrosamines etc. in broader water matrixes including recycled water, wastewater and drinking water.ā
Dr. Tanya Shvareva-Piekarz, Unit Supervisor
The Radiochemistry Unit (RCU) of DWRLB is the only State laboratory conducting radiological testing on environĀmental samples. RCU is capable of measuring alpha, beta, and gamma radioactivity in water, wastewater, sea water, air, biota, vegetation, milk, soil and other matrices and is certified by the US EPA to test regulated radioactive contaminants in drinking water. Radiochemistry services are provided to the Radiologic Health Branch (RHB), the Environmental Management Branch (EMB) and public health authorities and emergency responders at the local, State and Federal level.
RCU provides analytical support to the Radiologic Assessment Unit of RHB in monitoring environments surrounding the nuclear power plant sites in California by analyzing environmental samples for fission products which can reveal accidental releases. RCU monitors air samples throughout the State for ambient radiation. Air sampling stations are located in Eureka, Diablo Canyon, Livermore, Long Beach, Richmond, San Diego, San Luis Obispo, and San Onofre. Weekly air samplings detect airborne radioĀnuclides that could be released anywhere around the globe, for example, elevated radioactivity was measured for six weeks after the Chernobyl accident in 1986, and after the Tokaimura (1999) and Fukushima (2011) incidents. Another major area of work is enforcement/compliance and decommissioning/deconĀtamination. Radioactive materials are used widely in manuĀfacturing, research and hospitals throughout California, and these facilities require periodic testing for surface contamination. As sites are decommissioned, analyses of environmental samples are performed to demonstrate that radioactivity does not exceed background levels before these sites are released for unrestricted use.
RCU provides analytical support to the EMB in the cleanup of radiological materials at former military facilities prior to release from federal ownership. Currently soil samples from Treasure Island Naval Station and Hunters Point Naval Shipyard are being tested. Other sites McClellan Air Force Base, Alameda Naval Station and Mare Island Naval Shipyard have been tested for radioactive radium and strontium isotopes.
RCU is part of Californiaās Nuclear Power Plant Emergency Response Program (NERP) and is ready to receive environmental samples during the re-entry phase after a nuclear incident (e.g., accidents, dirty bombs, nuclear detonation). For this purpose, the lab is equipped with a special Semi-hot laboratory where moderately radioactive samples can be handled.
Research and method development is an important part of RCUās activities. Currently a rapid method for radioactive strontium in soil measurements as part of emergency preparedness expansion program is being developed. Other achievements include the development of methods for the detection of lead-210 and polonium-210 in water sources and detection of gross alpha and gross beta activities in water by liquid scintillation spectroscopy.
āMicrobiology & Biomonitoring Section
Dr. Alon Volner, Section Chief
*Vacant*, Unit Supervisor āāā
DWRLB houses CDPH environmental microbiology services and expertise in the Microbiology Unit (MU). The MU is accredited by The NELAC Institute (TNI) to perform microbiological water testing mandated by the federal Clean Water Act.
The MU specializes in detection of environmental pathogens and indicator organisms in water and wastewater matrices. The unit is part of the CA Surveillance or Wastewater (CalSuWers) program in CDPH, which is designated as a Center of Excellence by the CDC National Wastewater Surveillance System (NWSS) national program. The MU provides wastewater-based epidemiology (WBE) molecular testing and genomic sequencing for infectious disease monitoring of SARS Cov-2, influenza, RSV, MPOX and other pathogens in the wastewater to complement patient case incidences.
The MU is a CDC ELITE certified environmental testing laboratory targeting legionella spp. for outbreak response monitoring and manages a certified testing program for harmful algal bloom (HAB) toxinā monitoring for biological cyanotoxins in impacted surface and drinking water environments. The MU also served as the technical lead research lab in a special study with San Diego County Public Health (SDPH) that led to the first certified molecular-based rapid detection method in the U.S. for regulatory monitoring of fecal indicator bacteria, enterococcus spp., in coastal waters. The method is currently used by SDPH for daily water quality reporting and public notifications.
Dr. Wenlu Song, Unit Supervisor
The Biomonitoring Unit within DWRLB houses the Laboratory Response Network ā Chemical (LRN-C) laboratory at CDPH. The LRN-C laboratory network is coordinated by the Centers for Disease Control and Prevention (CDC) which supports 62 U.S. state, territorial, and major metropolitan labs through the Public Health Emergency Preparedness (PHEP) cooperative agreement and provides laboratory surge capacity for a public health emergency. The Level 1 LRN-C laboratory in DWRLB provides clinical testing of toxic chemical agents (e.g., including cyanide, nerve agents, mustard agents, metals, toxic industrial chemicals and biotoxins). The clinical testing is conducted using high-throughput, CDC test methods and instrument platforms for reliability, speed and capacity.