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:
Terrestrial
higher plant detritus (erosion, runoff)
plant waxes and pollen (atmospheric)
Aquatic
phytoplankton
zooplankton
Anthropogenic Sources:
Agricultural runoff
Vehicular engines (lube oil, exhaust residues)
POTW effluents (direct input)
Major natural compound groups in samples.
Compound Group
I. Homologous Series
n-Alkanes
n-Alkenes
n-Alkanals
n-Alkanoic acids
n-Alkanols
n-Alkanones
II. Molecular Biomarkers
Monoterpenoids (C10)
Sesquiterpenoids (C15)
Diterpenoids (C20)
Steroids
Isoprenoids
Wax esters
Plant Source
epicuticular waxes
alteration products
epicuticular waxes
internal lipid substances
epicuticular waxes
epicuticular waxes
essential oils
essential oils
gymnosperm resin, wax
internal lipid substances
internal lipid substances
epicuticular waxes
Major anthropogenic compound groups in samples.
Compound Group
Use
Alkylbenzenes
Nitro and polycyclic
musks
PAHs
PBDEs
Pesticides
Phenols
Phthalates
surfactants in detergents
fragrances in cosmetics,
personal care products
combustion products
flame retardants
pest control
antioxidants, preservatives
plasticizers
RESPONSE
50
40
30
20
10
20
30
40
n-C26
n-C27
Pentabromo diphenyl ether
n-C29
Hexabromo diphenyl ether
n-C30
n-C31
n-C23
n-C24
n-C25
n-C21
n-C22
n-C20
1-Methyl-undecylbenzene
1-Ethyl-undecylbenzene
1-Methyl-dodecylbenzene
BHT
n-C15
1-Methyl-nonylbenzene
1-Ethyl-nonylbenzene
1-Methyl-decylbenzene
kCounts
0
50
minutes
TIME
GC-MS total ion current trace of a 1994 river water
sample from Sacramento River, Rio Vista, showing
dissolved organic components (F1). Abbreviation:
BHT = butylated hydroxy toluene.
RESPONSE
125
100
75
50
25
150
20
30
Fluoranthene
Pyrene
40
n-C24al
Benzo[k]fluoranthene
Benzo[a]pyrene
n-C29
n-C31 n-C28al
Indeno[1,2,3-cd]pyrene
Benzo[ghi]perylene
n-C30al
C1-Pyrenes
Cyclopenta[cd]pyrene
n-C22al
S8
Phenanthrene
C1-Phenanthrenes
1,2,3,5-Tetrachloro-4,6-dimethylbenzene
Acenaphthene D10
kC ounts
0
UCM
50
60
m inutes
TIME
GC-MS total ion current traces of a 1993 sediment sample from
San Pablo Bay showing organic components (F2).
Abbreviations: S8 = elemental sulfur, UCM = unresolved
complex mixture.
20
30
40
50
Si
Cholesta-3,5-diene
Si
Si
Si
5
Si
Si
Galaxolide
4-Amino-musk xylene
Oxadiazon
U
U
10
C16 FAME
Musk ketone
15
C15 FAME
RESPONSE
20
U
Benzophenone
U
2,6-Di-tert-butyl-pbenzoquinone
U
kCounts
minutes
TIME
GC-MS total ion current trace of a 1993 water sample
from Dumbarton Bridge showing dissolved organic
components (F3). Abbreviations: FAME = fatty acid
methyl ester, Si = silicone, U = unknown.
Contaminants of Concern
Flame Retardants
Br
Br
Br
Br
O
O
Br
Br
Br
Br
Br
TetraBDE
PentaBDE
Br
Br
O
O
P O
O
O
Br
Br
Br
HexaBDE
Br
Triphenylphosphate
Sources: textiles, household and industrial products
Use: reduces flame capacity of materials
Max level: ppt (ng/L) Sacramento River water
Concern: endocrine system disruption, bioaccumulation
Surfactants
Anaerobic
metabolism
H(OCH2CH2)nO
p-Nonylphenol ethoxylates
(n= 1-15)
HO
Nonylphenol
Sources: household and industrial products
Use: lowers surface tension of water
Max level: ppt (ng/L) Sacramento River water
Concern: endocrine system disruption, bioaccumulation
Plasticizers
O
O
O
O
Di-n-butylphthalate
O
O
O
Butylbenzyl
phthalate
O
O
O
O
O
Bis(2-ethylhexyl)phthalate
Sources: household and industrial products
Use: adds flexibility to polymers
Max level: ppb (g/L) Dumbarton Bridge water
Concern: endocrine system disruption, bioaccumulation
Nitro and Polycyclic Musks
O2N
NO2
O2N
NO2
NO2
O2N
NO2
O2N
O
O
Musk
ambrette
Musk
ketone
O
NH2
NO2
Musk
xylene
4-Amino musk xylene
(metabolic product)
O
O
Galaxolide
Tonalide
Versalide
Sources: cosmetics and personal care products
Use: fragrances
Max level: ppb (g/L) San Pablo Bay water
Concern: bioaccumulation, toxicity
Antioxidants and Related Products
OH
OH
O
O
Butylated hydroxy Butylated hydroxy
toluene (BHT)
anisole (BHA)
O
OH
2,6-Di-t-butyl-4-hydroxy-4methyl-2,5-cyclohexadienone
4-Methylene-2,6-di-t-butyl2,5-cyclohexadien-1-one
O
OH
O
NO2
2,6-Di-t-butyl-pbenzoquinone
2,6-Di-t-butyl-4nitrophenol
Sources: preservatives in foods and cosmetics
Uses: prevents free radical oxidation
Max level: ppb (g/L) Sacramento River water
Concern: Unknown effects
Antioxidants and Related Products (continued)
OH
2,4,6-Tris(1-methyl-1phenylethyl)-phenol
OH
2,4-Bis(dimethyl)benzyl6-tert-butyl-phenol
OH
2,6-Bis(1,1-dimethyl)-4-(1-methyl1-phenylethyl)-phenol
OH
2,4-Bis(dimethyl)benzylphenol
Antiseptics
CH3
Cl
O
Cl
O
Cl
OH
OH
O
Cl
Cl
Cl
Cl
Triclosan
Methoxytriclosan
Chloroxylenol
Sources: consumer and personal care products
Use: preservatives and disinfectants
Max level: ppq (pg/L) waste water final effluent
Concern: toxicity
Herbicides
NO2
Cl
NO2
N
N
N
O2N
F
F
Benfluralin
F
O2N
F
Cl
O
N
O
Cl
Cl
O
O
Propyzamide
Cl
O
Oxadiazon
Cl
Cl
O
F
Trifluralin
O
Cl
N
F
O
Dacthal
Sources: urban and agricultural runoff
Uses: pest control
Max level: ppt (ng/L) San Pablo Bay water
Concern: toxicity
Pesticides
NO2
O
Cl
Cl
Cl
Cl
N
Cl
Quintozene
(fungicide)
Diethyltoluamide
(insecticide)
Sources: urban and agricultural runoff
Uses: pest control
Max level: ppt (ng/L) San Pablo Bay water
Concern: toxicity
Disinfectants
OH
Cl
Chlorophene
(bactericide)
O
O
Iridomyrmecin
(bactericide)
Source: household, hospital, and veterinary
disinfectants
Uses: antibacterial agents
Max level: ppq (pg/L) waste water final effluent
Concern: toxicity
Petroleum Products
R
R
R = C2H5 - C8H17
Extended tricyclic
terpanes
R
R = H, CH3, C2H5
R = H, C2H5, C3H7 - C8H17
Hopanes
Steranes
Sources: engine exhaust residues, seepage, oil spills
Use: fuel, lubricating oils
Max level: ppt (µg/kg) South Bay sediments
Concern: toxicity from UCM and PAH
Other Common Contaminants
O
CH3O
O
O
Octylmethoxy cinnamate
(UV blocker in sunscreens)
Retene
(conifer wood burning)
Benzophenone
(fixative in soaps)
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