POTW Pyrethroid Survey Results:Data Review and Summary

Yuzhou LuoCDPR/EM/SWPP

Overview

• 32 POTW facilities throughout California (one primary treatment, 18 secondary, 12 tertiary, one unknown)

• One sampling event for each POTW in early 2013• 8 pyrethroids (bifenthrin, cyfluthrin, cypermethrin,

deltamethrin, esfenvalerate, fenpropathrin, λ-cyhalothrin, permethrin)

• Reported data: whole-water concentrations in influent and effluent; concentration in biosolids

• Samples are not timed between influent, effluent, and biosolids collection

Detection FrequencyInfluent Effluent

bifenthrin 96% 82%cyfluthrin 88% 60%cypermethrin 81% 81%deltamethrin 43% 16%esfenvalerate 46% 32%fenpropathrin 4.5% 3.2%λ-cyhalothrin 81% 48%permethrin 100% 65%

Notes: [1] shows averages of detection frequencies by two Labs; [2] limits of detection (LOD) for influent are 4~10 times of those for effluent

Concentrations in EffluentThe maximum concentration (ng/L)

USEPA OPP aquatic life benchmark (ng/L)

Fish, acute

Fish, chronic

Invertebrates, acute

Invertebrates, chronic

bifenthrin 3.9 75 40 800 1.3

cyfluthrin 4 34 10 12.5 7

cypermethrin 13 195 140 210 69

deltamethrin 1.2 290 17 55 4.1

esfenvalerate 0.6 35 35 25 17

fenpropathrin 0.8 1100 91 265 64

λ-cyhalothrin 1.6 105 31 3.5 2

permethrin 170 395 51.5 10 1.4

Bifenthrin: Effluent Concentrations

Exceedance frequency

Detected only All samples

Primary 100% 100%

Secondary 29% 27%

Tertiary 0% 0%

Overall 22% 18%

Permethrin: Effluent Concentrations

Exceedance frequency

Detected only All samples

Primary 100% 100%

Secondary 100% 83%

Tertiary 100% 33%

Overall 100% 65%

Percent reduction by treatment types