Evaluation of Unknown Organic Contaminants

in the San Francisco Estuary

Daniel R. Oros and Nicole David

San Francisco Estuary Institute

Robert Risebrough

Bodega Bay Institute

Question asked by RMP investigators in 2000:

What are ALL the unknown peaks in the GC-MS

chromatograms?

Significance

first attempt at “surveillance monitoring”

makes system more “proactive” in identifying potential problem contaminants in the SF Estuary

Objectives

identify ALL the unknowns in the GC-MS chromatograms

estimate levels and determine distributions

link contaminants to known/suspected adverse impacts

target potential problem contaminants for monitoring

Methods

Samples (archived GC-MS full scan data):

SF Estuary water (93/94, along Estuary spine)

SF Estuary sediment (93, along Estuary spine)

Sacramento and San Joaquin river water (93/94)

POTW waste water final effluent (98)

Chemical Analysis:

sample solvent extraction and concentration

fractionation (3 each of increasing polarity)

gas chromatography-mass spectrometry (GC-MS)

Results

Natural Sources:

Terrestrialhigher plant detritus (erosion, runoff)plant waxes and pollen (atmospheric)

Aquaticphytoplanktonzooplankton

Anthropogenic Sources:

Agricultural runoffVehicular engines (lube oil, exhaust residues)POTW effluents (direct input)

Major natural compound groups in samples.

Compound Group Plant SourceI. Homologous Series

n-Alkanes epicuticular waxesn-Alkenes alteration productsn-Alkanals epicuticular waxesn-Alkanoic acids internal lipid substancesn-Alkanols epicuticular waxesn-Alkanones epicuticular waxes

II. Molecular BiomarkersMonoterpenoids (C10) essential oilsSesquiterpenoids (C15) essential oilsDiterpenoids (C20) gymnosperm resin, waxSteroids internal lipid substancesIsoprenoids internal lipid substancesWax esters epicuticular waxes

Major anthropogenic compound groups in samples.

Compound Group Use

Alkylbenzenes surfactants in detergentsNitro and polycyclic fragrances in cosmetics,

musks personal care productsPAHs combustion productsPBDEs flame retardants Pesticides pest controlPhenols antioxidants, preservativesPhthalates plasticizers

O

Br Br

Br Br

Br Br

O

Br

Br

Br

Br

BrO

Br Br

Br Br

Contaminants of Concern

TetraBDE PentaBDE

HexaBDE

Sources: textiles, household and industrial productsUse: reduces flame capacity of materialsMax level: ppt (ng/L) Sacramento River waterConcern: endocrine system disruption, bioaccumulation

P

O

O

O

O

Triphenylphosphate

Flame Retardants

Sources: household and industrial productsUse: lowers surface tension of waterMax level: ppt (ng/L) Sacramento River water Concern: endocrine system disruption, bioaccumulation

Nonylphenol

H(OCH2CH2)nOOH

Anaerobic metabolism

p-Nonylphenol ethoxylates(n= 1-15)

Surfactants

OO

O

OOO

O

O

O

OOO

Sources: household and industrial products Use: adds flexibility to polymersMax level: ppb (g/L) Dumbarton Bridge water

Concern: endocrine system disruption, bioaccumulation

Di-n-butylphthalate Butylbenzyl phthalate

Bis(2-ethylhexyl)-phthalate

Plasticizers

O

O2N NO2

Musk ambrette

O2N NO2

NO2

Musk xylene

O

O2N NO2

Musk ketone

O

Galaxolide

O

Versalide

NH2

O2N NO2

4-Amino musk xylene(metabolic product)

O

Tonalide

Sources: cosmetics and personal care productsUse: fragrancesMax level: ppb (g/L) San Pablo Bay waterConcern: bioaccumulation, toxicity

Nitro and Polycyclic Musks

OH

Butylated hydroxy toluene (BHT)

OH

O

Butylated hydroxy anisole (BHA)

Sources: preservatives in foods and cosmeticsUses: prevents free radical oxidationMax level: ppb (g/L) Sacramento River waterConcern: Unknown effects

Antioxidants and Related Products

O

O

2,6-Di-t-butyl-p-benzoquinone

O

OH

2,6-Di-t-butyl-4-hydroxy-4-methyl-2,5-cyclohexadienone

O

4-Methylene-2,6-di-t-butyl-2,5-cyclohexadien-1-one

OH

NO2

2,6-Di-t-butyl-4-nitrophenol

OH OH

OH

OH

2,4,6-Tris(1-methyl-1-phenylethyl)-phenol

2,4-Bis(dimethyl)benzyl-6-tert-butyl-phenol

2,4-Bis(dimethyl)benzyl-phenol

2,6-Bis(1,1-dimethyl)-4-(1-methyl-1-phenylethyl)-phenol

Antioxidants and Related Products (continued)

OH

Cl

Chloroxylenol

O

ClCl

Cl OH

Triclosan

O

Cl Cl

OCl

CH3

Methoxytriclosan

Sources: consumer and personal care productsUse: preservatives and disinfectantsMax level: ppq (pg/L) waste water final effluent Concern: toxicity

Antiseptics

F

FF

N

NO2

O2N

Benfluralin

F

FF

N

NO2

O2N

Trifluralin

O

NN

O

Cl

Cl

O

Oxadiazon

O

NCl

Cl

Propyzamide

Sources: urban and agricultural runoffUses: pest controlMax level: ppt (ng/L) San Pablo Bay waterConcern: toxicity

Cl

Cl

Cl

Cl

O

O

O

O

Dacthal

Herbicides

NO

Diethyltoluamide(insecticide)

Cl

Cl

Cl

Cl

Cl

NO2

Quintozene(fungicide)

Sources: urban and agricultural runoffUses: pest controlMax level: ppt (ng/L) San Pablo Bay waterConcern: toxicity

Pesticides

OH

Cl

Chlorophene(bactericide)

Source: household, hospital, and veterinary disinfectants Uses: antibacterial agentsMax level: ppq (pg/L) waste water final effluentConcern: toxicity

O

O

Iridomyrmecin(bactericide)

Disinfectants

Sources: engine exhaust residues, seepage, oil spillsUse: fuel, lubricating oilsMax level: ppt (µg/kg) South Bay sedimentsConcern: toxicity from UCM and PAH

R

R = C2H5 - C8H17

R

R = H, C2H5, C3H7 - C8H17

R

R = H, CH3, C2H5

Extended tricyclic terpanes

Hopanes Steranes

Petroleum Products

O

O

CH3O

Octylmethoxy cinnamate(UV blocker in sunscreens)

O

Benzophenone(fixative in soaps)

Other Common Contaminants

Retene(conifer wood burning)

Conclusions

most unknown peaks were identified (>90%)

levels ranged from pg/L (ppq) to g/L (ppb)

contaminants did not exceed lowest LC50 toxicity thresholds for most sensitive aquatic species

contaminants of concern were identified based on ability to bioaccumulate, induce toxicity, and persist

contaminants recommended for 2002 RMP monitoring:

Nitro and polycyclic musks (tissue only) Nonylphenol (water, sediment, tissue)PBDEs (water, sediment, tissue)Phthalates (water, sediment, tissue)Triphenylphosphate (water, sediment, tissue)

Future Work

analyze recent RMP tissue, sediment, and water samples for new contaminants

Acknowledgements

Dr. Wayne Sovocool, U.S. EPA Environmental Chemistry Branch, National Exposure Research Laboratory, Las Vegas, NV