ABSTRACT-
Background and Objectives:
Heavy metals exposure in animals can lead to profound effects in growth
and development. There have been incidences of various teratogenic effects in the past due to heavy metals exposure from
various sources. The present study was conducted to access the effect of chronic heavy metals exposure in animal models.
Materials and Methods:
An experimental prospective study was performed with viviparous animal Heterometrus fulvipes to access the cumulative effect of chronic heavy metals exposure. H. fulvipes was exposed with mercury and
lead; and effects monitored and documented in different times.
Results:
Chronic heavy metal exposure had considerable effects in mother and fetus of H. fulvipes. The effects in mother
were represented by the loss of body weight and decrease in hepato-pancreatic weight and hepato-somatic index. Chronic
exposure in fetus resulted in decrement in the embryonic length with subsequent reduction in the length and weight of
embryos.
Discussion:
These studies and results of heavy metals in animal have proved the harmful effects of chronic heavy metal
exposure with multitude of questions. The question of particular concern would be that how well animal teratology studies
will predict the human hazard. The primary area of focus could be on the prevention of the birth defects induced by
maternal exposure to heavy metals during pregnancy, as well as early prevention of teratogenic effects.
Conclusion:
It is necessary that the heavy metal toxicity be well documented in humans, and adequate precaution should
be taken in mother and fetus to decrease its detrimental effects in the long run.
Key-Words- Heterometrus fulvipes, Heavy Metals, Hepato-somatic indices, Morphometry
INTRODUCTION-
Heavy metals are known to affect the reproduction and
development of organisms. Heavy metals have different
sources: Mercury (Hg), Chromium (Cr), Nickle (Ni) and
Zinc (Zn) are mostly naturally occurring, whereas lead
(Pb), Cadmium (Cd), Copper (Cu) and Arsenic (As) are the
direct consequence of human environmental pollution [1]. The human health risk of heavy metals exposure is a public
health problem. The exposure of heavy metals, in particular
Pb, Cd, As and Methyl mercury (MeHg) directly interfere
with brain development and results in cognitive
impairment. The exact mechanism of their toxicity is still
unknown but their synergistic effect is well defined [2].
Much information has been accumulated on the toxicity of
the mercury and lead to humans. There are many reported
incidences of heavy metals poisoning due to potential
contamination, for instance arsenic and lead, leading to
lower cognitive scores in children [3-5]. Lead and mercury
toxicity are linked with the use of nutritional
contamination, ayurvedic supplements and skin creams
[6-7]. Seafood is one potential source of mercury, and it has
been recommended for limiting its use during the
pregnancy [8]. Heavy metals toxicity is implicated in
magnification of estrogen dependent disease in female, including cancer of breast, endometrium, and pregnancy
related complications like abortions, still births and
pre-term deliveries [9].
Mercury is a very toxic metal and there is no acceptable
level of mercury for animal exposure. Mercury can induce
damage in development of human at any period. It is a
potential neurotoxic, nephrotoxic and immunotoxic. The
prenatal exposure of methyl mercury, placenta being a very
ineffective barrier, can result in negative fetal impact to
central nervous system maturation. [10-11] Pregnant wistar
rats showed that mercury is capable of crossing the
placenta, accumulating in fetal organs notably highest
concentration in kidney, succeeded liver and brain [12].
Similar to mercury, lead exposures in rats have a profound
effect in their memory and overall cognition. [13] Exposure
of rats to high levels of lead has been associated with an
increased frequency of abortion and premature birth in
experimental animals.
It is evident that most of the studies on the effects of heavy
metals on the maternal animal with extended influence on
the embryonic development are confined to mammals and
fishes. Little information is available on other viviparous
forms, particularly the invertebrates, where viviparity and
long gestation period are known to exist. Identifying a good
viviparous model for evaluating the effect of heavy metals,
drugs and other xenobiotics on fetuses, when mother is
exposed or treated is of paramount importance. The
scorpion Heterometrus fulvipes with its long gestation
period is an ideal organism amongst invertebrates for a
study of how the heavy metals affect the embryonic
development when maternal animals are treated. An
attempt is, there for, made to study the effect of heavy
metals on the maternal animal and the embryonic
development of the viviparous invertebrate H. fulvipes. The
embryonic development depends upon the maternal
conditions as the mother provides the nourishment and
environment to the embryo.
Hence, it is likely that the effect of heavy metal on the
mother influence the embryonic development. To further
validate the extent of the influence, a study of the effects of
mercury and lead on embryonic development as reflected
by the changes in the morphological, morphometric and
gravimetric parameters of the embryos is undertaken.
Parturition is the pride of motherhood. A set of
physiological changes occur inside the body of mother
during pregnancy and parturition is the outcome of
successful embryonic development. The effect of heavy
metal on embryonic development, if any, would also reflect
in the parturition. Therefore, a study to access and
document the effects of the heavy metals on parturition
after the administration of cumulative long term doses were
performed and documented.
MATERIALS AND METHODS-
An experimental prospective study was conducted in the
department of Zoology, Nagarjuna University, Guntur
during April, 2011 to May, 2013 with H. fulvipes by using mercuric chloride and lead acetate to represent mercury and
lead respectively for studying the effect of these heavy
metals on the maternal and embryonic development.
The toxicity of mercury and lead was determined by
injecting different concentrations of the heavy metals
dissolved in distilled water into batches of test animals
through the arthrodial membrane in pedipalp between the
hand and the brachium. Control specimens were given
corresponding doses of distilled water. Mortality was
recorded after 24 hours, for each of the concentration
administered. LD50 value was calculated using Finney’s
probit method (Finney, 1964), and 1/3 LD50
(mercury- 0.042 mg/g body weight and lead- 0.58 mg/g
body weight) to be administered in the present study [14].
Gravid females collected during latter half of the July were
stocked in the laboratory in individual jars and maintained
feeding regularly with cockroaches. 1/3 LD50 value of
mercury and leadwere administered to the maternal animal
for monthly administration of sub-lethal doses of mercury
in successive doses during the gestation period. The stock
was divided into three groups. Group I received the sub
lethal dose of mercury, group II the sub lethal dose of lead
and Group III, as a control, received the corresponding
dose of solvent (Distilled Water).
After a month (mid-September), a batch of gravid females
was drawn from each group for studying the effects of first
doses of the heavy metals on the maternal animal, on the
embryonic development and on the parturition. Rest of the
animals in the three groups were administered a second
dose of the corresponding heavy metals by mid- September.
After taking samples from the three groups for
experimental purposes to evaluate the impact of second
dose by mid-October, the remaining ones were
administered a third dose. Similarly, the fourth, fifth, sixth,
seventh, eighth and ninth doses were administered by the
middle of November, December, January, February, March
and April respectively after drawing samples every month
for experimental purpose.
Gravid females drawn each month from the three groups
were individually weighed and the weight of the
hepato- pancreas of each animal was noted using a
monopan electrical balance (OWALABOR).
Hepato-somatic indices (HIS) were calculated using the
following formula:
HIS = (Weight of the Hepato-pancrease X 100)/Weight of the animal
Samples of gravid females drawn each month from the
groups I, II and III were sacrificed to examine cumulative
effects of successive monthly doses of mercury and lead on
the time course of development and on the morphological,
morphometric and gravimetric aspects of developing
embryos, using the corresponding group III samples
(distilled water treated animals) as controls. Now to study
the morphological features of the embryos, the maternal animals were dissected in scorpion Ringer’s solution and
the diverticula containing embryos were fixed in Bouins
fixative and preserved in 70% alcohol. Photographs of the
diverticula chosen at random were taken before isolating
the embryo to provide information on the size and shape of
the diverticula which are also known to change in
accordance with the development of the embryos. The
embryos in the diverticula were isolated and photographs
were taken for studying the morphological features of the
embryo for studying the morphometry, the length of the
embryo during the early month of gestation was measured
with the help of an ocular micrometer, in the later months,
lengths were measured using dividers, from the anterior
margin of prosoma to the tip of the metasoma. The average
length of the embryos in an animal was considered as the
length of the embryo of that animal. The values of lengths
obtained from a number of animals observed. For
gravimetric studies, the embryos were weighed together
with the diverticular membrane (excluding appendix and
oviduct). The average weight of the embryo in an animal
was considered as the weight of the embryo in that animal.
The values given in the data represent the means of such
values obtained from a number of animals examined.
Monopan electrical balance (OWALABOR) was used for
weighing the embryos.
To study the effect of mercury and lead on parturition, the
scorpions separated from each group every month and
maintained in the laboratory for delivery of young ones.
They were kept under observation till the end of June as
parturition in this species of scorpion always occurs during
May and June under normal conditions. The occurrence of
parturition, if otherwise was noted. When the parturition
occurred, the condition of the pulley (newborn young ones)
as reflected by its morphological features, length and
weight was noted. The pullies of those animals that
received different doses of mercury, and lead were
compared with those of the corresponding controls that
received distilled water.
RESULTS-
Effect of sub lethal doses of mercury and lead on
the maternal animal during the gestation period-
Sub lethal doses of mercury and lead administered to the
maternal animal at monthly intervals from August to April
induced changes in maternal body weight, weight of the
hepato-pancreas and hepato-somatic index (Tables 1-3;
Fig. 1-3). The reduction in the body weight was statistically
significant only after administration of fifth dose of
mercury and fourth dose of lead. A reduction of 25.33%
and 24.36% of body weight was recorded following
administration of ninth dose in the month of April for
mercury and lead respectively.
The weight of hepato-pancreas also has decreased
gradually in a dose dependent fashion leading to 13.77%
and 16.43% of depletion in April in response to mercury
and lead respectively, through the depletion was
statistically not significant (Table 2; Fig. 2) .
Table 1: Effect of mercury (Hg) and lead (Pb) on the maternal body weight of H. fulvipes during the gestation
period
| Month
Treatment |
Control Group |
Experimental group |
Percent depletion |
| AUG. |
7.287 + 0.166 |
Hg 7.246 + 0. 210* |
0.47 |
| Pb 7.170 + 0. 174* |
1.49 |
| SEP. |
7.510 + 0.170 |
Hg 7.360 + 0. 170* |
1.99 |
| Pb 7.259 + 0. 141* |
3.34 |
| OCT. |
7.260 + 0.249 |
Hg 7.105 + 0.140* |
2.13 |
| Pb 6.900 + 0. 152* |
4.95 |
| NOV. |
7.500 + 0.228 |
Hg 7.000 + 0. 235* |
6.66 |
| Pb 6.802 + 0. 166a |
9.30 |
| DEC. |
7.580 + 0.200 |
Hg 6.800 + 0. 103b |
10.29 |
| Pb 6.600 + 0.142c |
12.92 |
| JAN. |
7.560 + 0.196 |
Hg 6.440 + 0. 119b |
14.81 |
| Pb 6.400 + 0. 103c |
15.34 |
| FEB. |
7.800 + 0.182 |
Hg 5.960 + 0.136c |
23.59 |
| Pb 5.850 + 0. 151c |
25.00 |
| MAR. |
8.01 + 0.280 |
Hg 6.050 + 0.136b |
24.47 |
| Pb 5.856 + 0.152c |
26.89 |
| APR. |
8.21 + 0.339 |
Hg 6.130 + 0.148b |
25.33 |
| Pb 6.210 + 0.176c |
24.36 |
ap<0.05; bp< 0.01; cp< 0.001; *Insignificant
Values represent mean + S.E with number of observations (N) =10, Body Weight (g)
Table 2: Effect of mercury (Hg) and lead (Pb) on the weight of the hepatopancreas of H. fulvipes during the
gestation period
| Month
Treatment |
Control |
Experimental |
Percent depletion |
| AUG. |
1.574 + 0.123 |
Hg 1.450 + 0.114* |
7.87 |
| Pb 1.401 + 0. 113* |
10.99 |
| SEP. |
1.859 + 0.148 |
Hg 1.755 + 0.135* |
5.59 |
| Pb 1. 680 + 0.123* |
9.62 |
| OCT. |
1.773 + 0.123 |
Hg 1.654 + 0.123* |
6.71 |
| Pb 1.600 + 0.117* |
9.75 |
| NOV. |
1.700 + 0.135 |
Hg 1.566 +0.107* |
7.88 |
| Pb 1.509 + 0.117* |
11.23 |
| DEC. |
1.558 + 0.106 |
Hg 1.462 + 0.113* |
6.16 |
| Pb 1.390 + 0.100* |
10.78 |
| JAN. |
1.385 + 0.100 |
Hg 1.267 + 0.128* |
8.51 |
| Pb 1.200 + 0.135* |
11.19 |
| FEB. |
1.379 + 0.096 |
Hg 1.222 + 0.134* |
11.38 |
| Pb 1.200 + 0.130* |
12.98 |
| MAR. |
1.561 + 0.120 |
Hg 1.351 + 0.137* |
13.45 |
| Pb 1.309 + 0.140* |
16.14 |
| APR. |
1.539 + 0.122 |
Hg 1.327 + 0.134* |
13.77 |
| Pb 1.286 + 0.133* |
16.43 |
*Insignificant, Values represent mean+ S.E. with number of observations (N) = 10
Weight of hepato-pancreas (g)
Table 3: Effect of mercury (Hg) and lead on the hepatosomatic index of H. fulvipes during the gestation period
| Month
Treatment |
Control Group(8) |
Experimental group(10) |
Percent depletion |
| AUG. |
20.98 + 0.14 |
Hg 19.39 + 0.19c |
-7.57 |
| Pb 18.081 + 0.21c |
-13.81 |
| SEP. |
22.85 + 1.09 |
Hg 21.83 + 0.96* |
-4.50 |
| Pb 20.62 + 0.45a |
-9.79 |
| OCT. |
24.87 + 0.23 |
Hg 23.00 + 1.68* |
-7.51 |
| Pb 22.07 + 0.75b |
-11.25 |
| NOV. |
23.86 + 0.21 |
Hg 24.22 + 1.37* |
+1.52 |
| Pb 22.55 + 0.25c |
-3.44 |
| DEC. |
21.16 + 1.13 |
Hg 22.75 + 1.62* |
+7.51 |
| Pb 20.16 + 0.54* |
-4.72 |
| JAN. |
20.54 + 0.49 |
Hg 21.18 + 0.75* |
+3.11 |
| Pb 19.12 + 0.12b |
-6.88 |
| FEB. |
22.12 + 0.30 |
Hg 20.17 + 0.59a |
-11.10 |
| Pb 19.85 + 0.53b |
-12.51 |
| MAR. |
21.36 + 0.46 |
Hg 19.52 + 0.17c |
-8.59 |
| Pb 19.12 + 0.12c |
-12.85 |
| APR. |
20.00 + 0.66 |
Hg 18.80 + 0.20a |
-6.00 |
| Pb 18.49 + 0.16b |
-7.50 |
ap<0.05 ;bp< 0.01; c p< 0.001; *Insignificant
Values represent mean + S.E. with number of observations (N) given in parentheses
Hepato-somatic index
Table 4: Effect of maternal treatment with mercury (Hg) and lead (Pb) on the embryonic length during the
gestation period of H. fulvipes
| Month
Treatment |
Control Group(9) |
Experimental group(10) |
Percent depletion |
| AUG. |
1.25+0.09 |
Hg 1.23 + 0.11* |
1.99 |
| Pb1.21 + 0.11* |
3.58 |
| SEP. |
2.90+0.10 |
Hg 2.72 + 0.15* |
6.20 |
| Pb2.65 + 0.09* |
8.62 |
| OCT. |
3.15+0.15 |
Hg 2.83 + 0.11* |
10.15 |
| Pb 2.78 + 0.13* |
11.74 |
| NOV. |
4.42+0.15 |
Hg 3.50 + 0.15c |
20.85 |
| Pb 3.30 + 0.12c |
25.37 |
| DEC. |
4.83+ 0.16 |
Hg 4.00 + 0.12c |
17.18 |
| Pb 3.80 + 0.15c |
21.32 |
| JAN. |
7.01+0.20 |
Hg 6.05 + 0.12c |
13.70 |
| Pb 5.70 + 0.13c |
18.69 |
| FEB. |
13.00+0.22 |
Hg 8.58 + 0.15c |
34.00 |
| Pb 8.04 + 0.18c |
38.15 |
| MAR. |
15.50+0.26 |
Hg 12.09 +0.22c |
22.03 |
| Pb 11.20 + 0.28c |
27.77 |
| APR. |
16.50+0.33 |
Hg14.00 + 0.21c |
15.15 |
| Pb 13.10 + 0.21c |
20.60 |
cp< 0.001;* Insignificant
Values represent mean + S.E. with number of observations (N) given in parentheses
Hepato-somatic index
Table 5: Effect of maternal treatment with mercury (Hg) and lead (Pb) on the embryonic weight during the
gestation period of H. fulvipes
| Month
Treatment |
Control Group(8) |
Experimental group |
Percent depletion |
| AUG. |
1.5 + 0.18 |
Hg 1.4+ 0.15*(8) |
6.45 |
| Pb 1.3+0.13*(10) |
7.85 |
| SEP. |
2.5 + 0.08 |
Hg 2.2+0.11a(8) |
13.08 |
| Pb 2.1+0.14a (10) |
18.25 |
| OCT. |
3.5 + 0.13 |
Hg 3.0+0.10b (10) |
13.38 |
| Pb 2.8+0.11c (10) |
20.56 |
| NOV. |
6.1 + 0.25 |
Hg 4.9+0.20c(8) |
19.88 |
| Pb 4.7+0.18c(10) |
23.72 |
| DEC. |
13.1 + 0.10 |
Hg 11.3+0.29c(10) |
13.19 |
| Pb 11.0+0.40c (10) |
15.55 |
| JAN. |
17.4 + 0.36 |
Hg 15.5+0.46b (8) |
11.26 |
| Pb 14.0+0.23c (10) |
19.85 |
| FEB. |
32.4 + 0.75 |
Hg 24.0+0.23c(8) |
26.12 |
| Pb 22.0+0.47c(10) |
32.28 |
| MAR. |
55.6 + 0.82 |
Hg 39.3+0.27c (8) |
29.28 |
| Pb 39.0+0.24c(10) |
29.91 |
| APR. |
65.5 + 0.50 |
Hg 40.6+0.42c (8) |
37.93 |
| Pb 40.8+0.49c (10) |
37.64 |
ap<0.05 ;bp< 0.01; cp< 0.001; * Insignificant
Values represent mean + S.E. with number of observations (N) given in parentheses
Effect of mercury on pullies and parturition
Maternal animals that received a single dose of mercury in
August delivered young ones normally as those that
received second dose in September without any differences
in the duration of gestation period and length of the pullies.
However, a significant reduction in weight of the baby
scorpion was evident. Those scorpions that received three,
four, five, six, seven, and eight doses of mercury by
October, November, December, January, February and
march respectively also delivered young ones normally
after completion of gestation period along with the
controls. However, the size of the pullies as reflected by
their length and weight was significantly reduced, the
percent depletion being proportional to the number of doses
of mercury up to April failed to deliver young ones. On
examination in July (a month beyond the time of normal
delivery), it was found that all the young ones were dead
(Table 6).
Table 6: Effect of maternal treatment with mercury (Hg) and lead (Pb) during the gestation period on the length of
pullies of H. fulvipes
| Month
Treatment |
Control Group |
Experimental group(10) |
Percent depletion |
| AUG. |
16.7 + 0.10 |
Hg 16.4+ 0.12* (10) |
1.675 |
| Pb 16.3+0.10a (10) |
2.189 |
| SEP. |
17.1 + 0.19 |
Hg 16.7+ 0.10*(10) |
2.214 |
| Pb 16.6+0.14a(10) |
3.263 |
| OCT. |
16.8 + 0.16 |
Hg 16.1+ 0.14a (10) |
4.223 |
| Pb 15.9+0.14b (10) |
5.413 |
| NOV. |
16.6 + 0.10 |
Hg 15.4+ 0.20b(10) |
7.151 |
| Pb 15.5+0.19c (10) |
6.851 |
| DEC. |
16.8 + 0.14 |
Hg 15.2+ 0.19c (10) |
9.846 |
| Pb 14.9+0.19c(8) |
11.621 |
| JAN. |
16.4 + 0.12 |
Hg 14.4+ 0.13c(7) |
12.621 |
| Pb 14.0+0.17c(4) |
14.805 |
| FEB. |
16.5 + 0.07 |
Hg 14.0+ 0.15c(5) |
15.254 |
| Pb 13.5+0.17c(2) |
18.280 |
| MAR. |
16.8 + 0.08 |
Hg 14.0+ 0.17 |
17.010 |
| Pb Parturition did not occur |
|
| APR. |
16.7 + 0.10 |
Hg Parturition did not occur |
|
| Pb parturition did not occur |
|
ap< 0.05; bp< 0.01; cp< 0.001; * Insignificant
Values represent mean + S.E. with number of observations (N) given in parentheses
Length of pullies (mm)
The hepato-somatic indices following the administration of
lead were significantly lowered throughout the gestation
period. Mercury exerted relatively lesser influence, the
depletion during November, December and January being
resulted in general, cumulative effect of mercury also
resulted in reduction of the indices (Table 3; Fig. 3).
Effect of sublethal doses of mercury and lead on
the embryonic development during the gestation
period:
Effect on morphological differentiation-
Examination of diverticula and the embryos contained
within at any time during gestation period both in the
controls and the experimental animals treated with sub
lethal doses of mercury and lead from August to April,
revealed no differences in the sequence of morphological
differentiation as could be noted (Figs. 4 to 12), except for
difference in the size, with the sequence and time course of
embryonic development remaining the same in both
controls and experimental animals, the gestation period
appears to remain unaltered.
Effect of mercury and lead on the embryonic
length and weight-
The administration of sub lethal doses of either mercury or
lead to the maternal animal during gestation period from
august to April resulted in reduction in embryonic length
exhibiting a cumulative effect (Table 4). The decrease in
length tended to increase gradually with an insignificant
effect up to October and highly significant effect beyond.
Sub lethal doses of mercury and lead administered to the
pregnant females during gestation period caused a very
significant reduction also in the weight of embryos.
Gradually increasing percentage of depletion in the
embryonic weights up to a maximum of about 38% from
august to April reflected a dose dependent effect for both
the metals (Table 5).
Administration of sub lethal concentrations of lead to
pregnant scorpions during the gestation period also had
comparable effects. All females that received a single dose
or two or three or four up to seven doses delivered young
ones without any difference in the duration of gestation
along with the controls. The pullies were, however,
significantly lesser in length and weight compared to those
of the controls. A cumulative effect of lead was evident as
reflected by the gradually increasing percentage of
reduction in lengths and weights of the pullies in
accordance with the increase in the number of doses
administered (Table 6). In females that received more than
seven doses of lead, parturition did not occur. The long
term cumulative effect of lead was fetocidal as evidenced
by the dead young ones within the diverticula when
examined during July, a month beyond the time off normal
parturition.
DISCUSSION-
The result obtained in the present study reveal that there is
a well recognizable impact of the heavy metals, mercury
and lead, on the maternal animal resulting in the loss of
body weight and weight of hepato-pancreas and
hepato-somatic index. The decrease in the body weight and
the weight of the hepato-pancreas of
H. fulvipes, following
the administration of the heavy metals can be explained in
terms of altered metabolic levels and increased utilization
of reserve stores by the animal for its maintenance and for
the maintenance of the developing embryos on the face of
the excessive energy demands under the toxic stress of the
heavy metals. The decline in the hepato-somatic indices
together with decrease in the weight of the hepato-pancreas
of the animals treated with mercury and lead suggest a
preferential utilization of liver components.
In
H. fulvipes treatment with cumulative doses of mercury
and lead significantly reduced the length and weight of the
embryos. The effect of cumulative doses of heavy metals
on embryonic development is reflected in a new born also
resulting in significantly reduced lengths and weights of the
young ones. The observed reduction might possibly be due
to lowered availability of nutrients owing to the increased
utilization of reserves by the mother under heavy metal
toxicity, or decrease in the organic reserves of the embryos
due to direct effect of heavy metals or due to competitive
utilization by the mother and the embryo under heavy metal
stress condition. Failure of parturition observed in the
present study in animals that received eight doses of
mercury and seven dose of lead, could be attributed to the
cumulative effect of the repeated doses of heavy metals. It
may also be suggested that the duration of stresswas
inadequate to prevent parturition during the eight doses of
mercury and seven doses of lead.
These studies and results of heavy metals in animal have
definitely raised a multitude of questions. The question of
particular concern would be that how well animal
teratology studies will predict the human hazard. The focus
should be on the prevention of the birth defects induced by
maternal exposure to heavy metals during pregnancy.
CONCLUSION-
There is a significant effect of heavy metals in mother and
fetus. In view of the fact that the loss of weight under the
heavy metals stress is suggested to be due to the excess
utilization of reserve stores, if it is felt desirable that a
detailed investigation on the biochemical constituents of
animals exposed to heavy metals is carried out. It will also
help to have an insight into the extent to which the impact
of heavy metals on the biochemical constituents of the
maternal animal extends into the embryonic development
holding responsibility for the observed effects of the heavy
metals on the embryos of
H. fulvipes. Therefore, it is
pertinent that this information should be reflected to
humans and more-research should be conducted to explore
the effect of heavy metals in growth and developments.
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How to cite this article:
Raghavendra Rao MV, Acharya Y, Bala AS, Paramben S, Sowmya K, Raj BV: Study of Heavy Metals in Abnormal Growth and
Development using an Alternate Animal Model: Heterometrus fulvipes. Int. J. Life. Sci. Scienti. Res., 2017; 3(1): 800-807.
DOI:10.21276/ijlssr.2017.3.1.9
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