Effects of Benzene on Brine Shrimp, Artemia franciscana

1
Effects of Benzene on Brine Shrimp, Artemia
franciscana Kendall Asper (Dr. Nicole Okazaki),
Spring 2008 Weber State University, Department of
Zoology Ogden, UT 84408
Results
However, the shrimp were exposed for only 24
hours to the TCB and their life parameters were
subsequently observed (Grosch, 1973). Crude oils,
in concentrations ranging in the part per
thousand, killed most shrimp within three hours
(Trieff, 1980).  These crude oils contain many
toxic compounds, with benzene among them.
  Benzene has wide ranging effects in cells,
triggering genotypic damage resulting in
leukemias and other types of cancers (Medlin,
2003).  While the SDS-PAGE study does not
identify which proteins are affected, it points
to changes occurring in the cells.  Some of the
proteins affected might be the heat-shock
proteins 70 and 90.

• Figure 3 Number of Broods

• Acute exposure While only 1.1 of larvae died
  in the control, the mortality rates were 30.1
  and 4.0 after exposure to 10-3 and 10-2 (v/v)
  benzene solutions, respectively.
• 24 hr. acute exposure to benzene solution of 10-2
  (v/v) was 50.0 fatal to adult shrimp while all
  survived in 10-3 (v/v) benzene solution and in
  the control.
• SDS-PAGE showed an increasing expression of some
  proteins with increasing benzene concentration
  (see Figure 1).
• Western Blot showed increasing expression of
  proteins with an affinity to antibodies used to
  identify heat shock proteins (see Figure 2).
• Mean time to maturation for brine shrimp were
  27.8 days for controls, 29.4 days for 10-5 (v/v)
  benzene solutions, and 29.6 days for 10-4 (v/v)
  benzene solutions.

Number of Broods
Introduction
The Great Salt Lake is a terminal lake highly
susceptible to contamination . Benzene, a
volatile organic compound (VOC) and waste product
of crude oil distillation, has been detected in
water near residential and commercial areas
surrounding Salt Lake City (Thiros, 2000). This
experiment was designed to determine the
physiological effects of benzene on one of the
Great Salt Lakes native species, Artemia
franciscana.

• Figure 4 Mean number of cysts/larvae per brood

Figure 1 SDS-PAGE proteins taken from adult
brine shrimp exposed to benzene for 24 hrs.
Lanes furthest left and right are protein
ladders. Benzene concentrations are from left to
right as follows Control, 10-6, 10-5, 10-4,
10-3, 10-2.
Discussion
Methods
Under short term laboratory exposure, Artemia
larvae and adults have a high tolerance to
benzene, with mortality occurring at high
concentrations of 10-2 and 10-3 (v/v). Under
chronic exposures of 10-4 and 10-5 (v/v) the
maturation time was not affected the number of
shrimp that reached maturation, especially the
females, were dramatically decreased.  The
presence of benzene appears to have a direct and
proportional deleterious effect on the number of
eggs produced per brood. Very few studies about
the effect of benzene on Artemia have been
found.  Similarly to our study, exposure to a
derivative of benzene, TCB, increases mortality,
especially in females, and sharply reduces the
number of eggs. 
Literature Cited

• Acute exposure Survival of adult and larval
  Artemia were observed after 24 hour exposure to
  3 seawater (SW) solutions containing benzene
  concentrations ranging from 10-2 to 10-8 (v/v).
• The level of expression of heat shock proteins
  hsp70 and hsp90 were visualized in adult shrimp
  exposed to sub-lethal doses of benzene, 10-4 and
  10-5 (v/v), for 24 hours, using SDS-PAGE and
  Western Blot assays.

Grosch, Daniel S. 1973. Reproduction Tests The
Toxicity for Artemia of Derivatives from
Non-Persistent Pesticides. Biol. Bull.
145340-351. Thiros, Susan A. 2000. Quality of
Shallow Ground Water in Areas of Recent
Residential and Commercial Development in Salt
Lake Valley, Utah, 1999. USGS Fact Sheet
FS-106-00. Medlin, J.  2003. Benzene adverse
effects microarrays reveal breadth of toxicity. 
Environmental Health perspectives, 111(11)
590-591.  Trieff. N.M.  1980.  Toxicity of
heavy metals, oils and other organics on Artemia.
in. The Brine Shrimp Artemia, Vol. 1. 
Morphology, genetics, Radiobiology, Toxicology.
G.Persoone, P. Sorgellos, O. Roels, and E.
Jaspers (Eds). Universa Press, Wetteren, Belgium,
p253-263. 
Figure 2 Western Blot the image to the left was
treated with hsp70 antibodies and the image to
the right was treated with hsp90 antibodies. The
lanes, from right to left, are the ladder
control, 10-6, 10-5, 10-4, 10-3, 10-2.

• Chronic exposure The effect of benzene
  concentrations of 10-4 and 10-5 (v/v) on the
  maturation rate and fertility was measured. For
  each treatment, seventy larvae were raised in 50
  ml benzene solutions of 3 SW with algae.

Acknowledgements
A special thanks to the Office of Undergraduate
Research for this opportunity.