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C  O N TA M I N A N T A  C C U M U L AT I O N

ORITY ON

D7

RI

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TH

EF

S FOR HEAL

What

What Is It?

BENCHMARK

This indicator is a direct measure of the types and

Establish baseline values of "current"

Establish

quantities of chemical compounds (particularly

levels for different species and areas,

agrochemicals) accumulating in the tissues of

marine organisms and the sediments of marine

Determine short-term benchmarks for

environments.

contaminant

contaminant reductions.

Some contaminants found in the marine environment

TA R G E T

are associated primarily with agricultural activity (e.g.,

many fungicides and herbicides). Others (insecticides

Reduce

Reduce contaminant levels in

such as chlorpyriphos, malathion, or heavy metals) are

sediments and marine organisms to

also associated with golf courses, mosquito control

acceptable limits (to be determined).

acceptable

programs and urban runoff.

RED FL AG

Why Do We Measure It?

Any

Any increase in contaminant

Although corals and other reef organisms have been

concentrations from (current 2006

the subject of few ecotoxicology studies, they are

levels) in marine organisms or sediment

generally thought to be highly sensitive to chemical

samples.

perturbations (particularly in larval development

and settlement phases)19. Many chemical products

used for inland applications (e.g., pest control) can

WWF/ICRAN describes field and laboratory methods

be transported via rivers to the sea, where they

for analyses of mustard hill coral (Porites asteroides),

eventually accumulate in sediments or the tissues of

queen conch (Strombus gigas), white grunt (Haemulon

marine organisms. As a result, even chemicals applied

plumierii) and surface sediments22. The MBRS

far inland may have imperceptible but significant

Synoptic Monitoring Program also contains a protocol

consequences on the condition and persistence of

for sediment collection and analysis of fish tissue

coral reefs.

for biomarkers of stress associated with chemical

contaminants23.

Some compounds bind to sediment or organic matter

that settles out in coastal environments. Others are

Usefulness

Usefulness

lipophilic (fat-loving) and quickly become incorporated

into plankton, invertebrates, and fish through the

The accumulation of contaminants is a strong indicator

process of bioaccumulation through food webs.

of agricultural activity (and, to some extent, general

Others remain dissolved in the water for long periods,

coastal development). Some of these chemicals are

more slowly being incorporated into filter feeders and

carcinogens, others endocrine disruptors, and others

other marine life.

may interfere with neurological development or

other physiological processes. The potential impacts

There is some recent evidence that coral bleaching

of chemical contaminants are of concern to both

can occur at lower temperatures if the coral is stressed

marine life and the human populations that consume

by either agrochemicals or sediments20. Other recent

these marine organisms (measured in indicator SW1

studies have shown detrimental effects to coral planula

­ Contaminants in Breast Milk). When considered in

survival and settlement success when exposed to low

conjunction with coastal development and agricultural

concentrations (~ 5 ppb) of some agrochemicals (e.g.,

input indicators, the linkages between these activities

chlorothalonil and Irgarol)21.

and potential health implications can be identified

How Do We Measure It?

more readily.

While some chemicals of concern (e.g., chlorothalonil)

Agrochemicals  and  other  contaminants  can

may be fairly specific to certain agricultural crops

be measured directly from tissue samples and

(e.g., bananas), other chemicals (e.g., malathion) also

sediments. A sampling protocol recently developed by

have non-agricultural uses. Furthermore, complex

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