Hiran M. Dutta

Effects of endosulfan on brain acetylcholinesterase activity in juvenile bluegill sunfish

The effects of endosulfan upon brain acetylcholinesterase (AChE) activity were measured in juvenile bluegill sunfish (Lepomis macrochirus). Based on exposure durations of 0, 24, 48, 72, and 96h and 1 week at 1.0 microg/L (just below the LC50 of 1.2 microg/L for this species), step-wise decreases in AChE activity were noted, corresponding to 0%, 3.57%, 12.65%, 14.23%, 16.31%, and 23.11% inhibition, respectively. Total brain protein concentrations were measured to test the accuracy of the AChE data with no significant anomalies. The duration of exposure was related to the reduction in the AChE activities which reflected the biotoxicity of endosulfan. The changes in the AChE activities will certainly affect the normal behavior of the juvenile bluegill which is detrimental to their very existence in the natural habitat.

Histopathological changes induced by malathion in the gills of bluegill Lepomis macrochirus

Malathion is a widely used broad spectrum organophosphorus insecticide. Its wide use provides many occasions for its entry into aquatic environments. The presence of this chemical in the aquatic environment would adversely affect many non-target species like fish. About 50 to 90% of the absorbed malathion can be eliminated in one to three days by the fish. About 25% of malathion remained in river water after 2 wk, and 10% remained after 4 wk from the time of its entry. Respiratory distress is one of the early symptoms of pesticide poisoning. These toxicants appear to cause a loss of adhesion between the epithelial cells and the underlying pillar cell system, accompanied by a collapse of the structural integrity of the secondary lamellae. Gills are important in respiration as well as osmoregulation of the fish. Therefore it was decided to study the effects of malathion on the gills of bluegill sunfish, Lepomis macrochirus. Bluegills were selected for this study due to the following reasons: (1) Bluegills are more sensitive to malathion when compared to fathead minnows and goldfish. (2) They are important both as edible and game fish. (3) They are easily available and easy to maintain in the laboratory.

Fish morphology : horizon of new research

Topics covered in this volume include: transformation morphology on structures in the head of cichlid fishes the structure and function of fish liver atretic follicles and corpora lutea in the ovaries of fishes effects of gill dimension on respiration and the efects of pesticides on fish.

Effect of malathion on the brain acetylcholinesterase activity of bluegill sunfish Lepomis macrochirus

The harmful e f f e c t s o f p e s t i c i d e s on a q u a t i c organisms a re due t o the i n d i s c r i m i n a t e use , c a r e l e s s hand l ing , a c c i d e n t a l s p i l l a g e , o r d i s c h a r g e o f u n t r e a t e d e f f l u e n t s i n t o n a t u r a l waterways. There was a s h i f t in the t y p e s o f i n s e c t i c i d e s used in the mid-1960s from the o r g a n o c h l o r i n e to the l e s s s t a b l e o rganophospha te and carbamate c l a s s e s (Henry 1984). Mala thion be longs to the wide ly used organophosphorus group of p e s t i c i d e s . Mala th ion has a low t o x i c i t y to mammals and a r e l a t i v e l y h igh t o x i c i t y to f i s h (Mount and Stephan 1967). I t r eaches the a q u a t i c environment by d i r e c t a p p l i c a t i o n , sp ray d r i f t , a e r i a l s p r a y i n g , washing from the a tmosphere by p r e c i p i t a t i o n , e r o s i o n and r u n o f f from a g r i c u l t u r a l land , in f a c t o r y e f f l u e n t s and in sewage (Edwards 1973). Frank e t a l . (1990) surveyed the farm we l l s du r ing 1986 and 1987 f o r p e s t i c i d e s in O n t a r i o , Canada. The i r su rvey showed c o n t a m i n a t i o n o f farm we l l s by v a r i o u s p e s t i c i d e s i n c l u d i n g ma la th ion .

Histological examination of sublethal effects of diazinon on ovary of bluegill, Lepomis macrochirus

The effects of the insecticide, diazinon (an organophosphorous compound), on the ovaries of bluegill (Lepomis macrohirus) were studied. Histological preparations of bluegill ovarian tissue was examined at 24, 48, 72 and 96 h and 1, 2 and 3 weeks following exposure to sublethal doses of diazinon (60 microg/l). The control contained primary follicles with an intact ovigerous lamellae and tunica albuginea. The control also revealed well developed stage IV oocytes with properly distributed provitelline nucleoli. After 24 h of exposure to diazinon, primary follicles began to show adhesion and cytoplasmic retraction in oocyte II occured. Cytoplasmic degeneration and additional adhesion and more retraction were visible at 48 h in oocyte II; 72 h brought forth adhesion, retraction and cytoplamic expulsion from oocyte IV. The number of atretic oocytes increased. Damages to the oocyte IV started to occur after 72 h of exposure. Cytoplasmic retraction and clumping was more visible at 96 h in oocyte IV. Partial destruction of the ovigerous lamellae and vitellogenic membrane occurred after 1 week. Two weeks continued to reveal destruction of follicles. Severe damage of the ovigerous lamellae, increased intrafollicular spaces, vacuolated cytoplasm, extrusion of karyoplasm and necrosis in the cytoplasm were most evident following 3 weeks of exposure. The ovarian wall became frayed and broken. Additionally, a marked increase of atretic follicles, shrinkage, and embedded nucleoli into the surrounding cytoplasm in oocyte II, III and IV were observed at week 3. This study revealed that oocytes at their different stages of maturation get affected differently at various exposure. Based on observations of the ovarian tissue compositional and structural changes following given exposure times, it becomes evident that consistent sublethal doses of diazinon can and will alter microscopic anatomy of the fish ovary.

Age related differences in the inhibition of brain acetylcholinesterase activity of Heteropneustes fossilis (Bloch) by malathion

Abstract The objective of this study is to determine whether there are differences in the sensitivity of brain acetylcholinesterase between juvenile and adult fish exposed to malathion. Air-breathing catfish, Heteropneustes fossilis were used. The exposure concentration was 1.2 mg/l (sublethal), and exposure durations were 24, 48, 72, and 96 hr. A reduction in the mean acetylcholinesterase activity is seen at all exposure durations in the juveniles. It also indicates a significant difference between the control and exposure groups-24, 48, 72 and 96 hr in group A. However, in the adults, a reduction is seen, only at the 72 hr exposure duration. T -value and two-tail probability show that only control and 72 hr exposed ones are significantly different. In the higher weight group, there is a recovery in AChE activity at the 96 hr exposure level. This indicates that the detoxification capacity of the fish increases with age. The results show that the juveniles are much more susceptible than the adults.

Ultrastructural changes in the respiratory lamellae of the catfish, Heteropneustes fossilis after sublethal exposure to malathion.

Transmission electron microscopy study of the gills of Heteropneustes fossilis, exposed to 4 mg/liter of malathion (1/3 of LC50) for 24, 48, 72, and 96 h showed significant changes in its ultrastructures. Exposure to the pesticide after 24 h caused a slightly disarrayed condition in the double layered epithelial structure. Lymphatic spaces became more apparent, and a few chloride cells appeared which protruded toward the peripheral margin of the secondary lamellae. Chloride cells were exposed to the exterior by an apical pit. Pinocytosis was observed with marginal folds (MF) originating from the pillar and epithelial cells. Some vascular constrictions were also seen in the capillaries with erythrocytes. After 48 h exposure, the outer epithelial cells were stretched into a thin boundary wall and lymphatic spaces were engorged with plasma exudate. Chloride cells transversed the whole epithelium of the lamella and came into direct contact with lymphoid space and exterior to epithelial lining. Basement membrane of the capillaries became thicker. After 72 h a distorted lamellar epithelium ruptured in a few places allowing many spheroid bodies and some chloride cells come out. Marginal folds of pillar cells migrated into vascular spaces. Basement membrane of capillaries became thicker and blood channels were constricted causing vascular stasis. No erythrocytes were visible. Blood channels were filled with leukocytes and amoebocytes. After 96 h exposure to malathion narrowing of lymphatic spaces, proliferation of epithelial cells and development of pinocytotic vesicles from marginal folds of pillar cell flanges were observed. Only marginal blood channels maintained normal configuration. Vascular stasis due to thickening of the basal lamina were still evident in centrally located blood channels filled with leukocytes. Vascular stasis would likely cause a decrease in respiratory efficiency. This study has revealed that the gills of H. fossilis were affected by a sublethal dose of malathion. The ultrastructural damages to the gills were observed as early as at 24 h exposure, but the most severe damage occurred at 72 h exposure. However, signs of gill structure regeneration were seen in malathion-exposed fish after 96 h.

Effect of malathion on the optomotor behavior of bluegill sunfish, Lepomis macrochirus

1. Behavioral changes are very good and sensitive indicators of pollution by any toxicant. The optomotor responses are useful to quantify the changes in some of the movement patterns of the fish. 2. The present study deals with the behavioral changes of bluegill sunfish, Lepomis macrochirus, that result from an exposure to 0.002, 0.004, 0.008, 0.016, 0.032 and 0.048 ppm of malathion. 3. Malathion belongs to the widely used group of organophosphorus pesticides. Alterations in behavior due to an exposure to sublethal concentrations of malathion were estimated by measuring two parameters namely “following” and “reversal” which involve two optomotor responses. 4. A specially constructed apparatus with a jar containing water to hold the fish around which was a rotating patterned drum was used to measure the optomotor response. 5. All 90° changes in movements or turns, referred to as “quarter turns”, made by the fish in the direction of the drum rotation (“following”) or opposite direction (“reversal”) were recorded. 6. At 0.016 ppm exposure level the fish became hyperactive and at 0.048 ppm exposure level they became lethargic. 7. The mean scores for “following” was significantly (P < 0.0001) different at 0.016, 0.032 and 0.048 ppm exposure concentration compared to control, 0.002, 0.004 and 0.008 ppm exposure concentrations. 8. The mean “reversal” scores showed more or less the same trend. 9. There was a significant (P < 0.0001) increase in “reversals” at 0.016 ppm compared to control and fish exposed to various other concentrations. 10. Behavioral studies may be used to quickly assess and evaluate the effects of sublethal doses of pollutants that are found in very small quantities in the aquatic environment.

Geographical Patterns of AIDS in the United States

Data on incidence of AIDS between 1981 and 1986 from the U.S. Centers for Disease Control are analyzed geographically. Nationwide and regional patterns by source groups, gender, race, age cohorts, and survival rates in the United States are emphasized. Some elements like association of AIDS incidence by source display distinct regional variations, while others like incidence by age cohort have uniform patterns. A CQUIRED immune deficiency syndrome (AIDS) is the bubonic plague of the twentieth century. Both diseases were initially incurable, and, as was the case with the plague, almost everyone who contracts AIDS eventually dies of it. Contrastingly the cause of AIDS was discovered and isolated shortly after the disease was identified.1 In this article we offer a spatial analysis of the disease in the United States by region, by patient, gender, and age groups of the victims, and by country of birth and death. This analysis is both tentative and speculative. Because of the current status of data collection and reporting for AIDS, definitive conclusions are virtually impossible. However, the problem has such contemporary enormity and future implications that it cannot be ignored or withheld from geographical analysis. The deadliness of AIDS is unquestioned. According to the World Health Organization, more than 500,000 AIDS cases had been reported globally by mid-1987, and five to ten million persons in all parts of the world had been infected by the virus.2 By the end of 1986, 32,560 cases had been reported in the Western Hemisphere, and 90 percent of them were in the United States. From the initial four diagnoses in 1978, the number of new cases in the United States increased to nine in 1979 and to forty-four in 1980.3 In 1986 alone, 9,877 new cases were reported by the U.S. Centers for Disease Control (CDC). The origin of the AIDS virus has several possible explanations. Most researchers believe that the retrovirus responsible for AIDS originated in * Margaret Geib, cartographer for the Department of Geography, University of Akron, prepared the graphics. Bani Bose, librarian at Akron City Hospital, Swati Sinha, and Karen Schauri are thanked for their help in the research for this article. I Colin Norman, AIDS Priority Fight Goes to Court, Science 231 (3 Jan. 1986): 11-13; Colin Norman, AIDS Virology: A Battle on Many Fronts, Science 230 (29 Nov. 1985): 518-521. 2 Jean L. Marx, Probing the AIDS Virus and Its Relatives, Science 230 (19 June 1987): 1523. 3A. M. Hardy, James R. Allen, W. Meade Morgan, and James W. Curran, The Incidence Rate of Acquired Immune Deficiency Syndrome in Selected Populations, Journal of American Medical Association 253, No. 2 (1985): 215-220. * DR. DUTT and DR. MONROE are members of the geography faculty at the University of Akron, Akron, Ohio 44325, where MRS. PRINCE is a graduate student in urban studies. DR. DUTTA is an associate professor of biological sciences at Kent State University, Kent, Ohio 44242. This content downloaded from 157.55.39.135 on Sun, 03 Jul 2016 04:14:23 UTC All use subject to http://about.jstor.org/terms AIDS IN THE UNITED STATES 457 Africa.4 The disease has been recognized in central Africa at least since 1972, six years before its identification in the United States. The large number of cases recognized in central Africa earlier than in other regions of the world suggests an African origin and the spread of the AIDS virus from there. This explanation of the origin of AIDS emanates from the isolation of a retrovirus, similar to the AIDS virus, from West African wild green monkeys. The virus may recently have crossed the species barrier and infected humans, although the green monkeys with the virus remained devoid of AIDS. Thus the monkey virus may be mutated in humans and may have acquired some destructive properties.5 Two other explanations have been postulated.6 The AIDS virus may have been present in a small number of humans for a long time, but only recently did the number become large enough for the disease to be identified. The recent increase in cases may result from various factors such as changing migration patterns and rises in intravenous drug abuse and homosexuality. Another possibility is that the AIDS virus is a variant of a retrovirus that has always infected humans. The data for this study come from AIDS-case reports received by the U.S. Centers for Disease Control as of January 1987. These data are reported voluntarily by state and local health departments and are compiled on a Public Information Data Tape by the CDC. Information for each victim includes age at and date of first diagnosis; race; large SMA region (Northeast, Central, West, South, Mid-Atlantic) or small SMA; country of birth and, if patient is deceased, of death; and gender (male, subdivided into homosexual, bisexual, or heterosexual, and female). Information is also available for relevant patient groups: homosexual/bisexual male, intravenous drug user, a combination of these two, hemophiliac, heterosexual contact with an AIDS victim, or transfusion recipient. Through January 1987, the total sample included 29,137 AIDS patients. These data were cross-tabulated to examine relationships among the characteristics of each AIDS victim. The annual incidence rates of AIDS victims per 100,000 persons for the years 1981 to 1985, 1986, and 1987 appear on figures 1 and 2. Because statewide data were not available for individual years from 1981 to 1985, the five-year total for each state was divided by five to obtain an average for the period. Although the disease was primarily concentrated in large cities, only statelevel data were available nationwide. Hence choropleth maps were based on states. Incidence in the District of Columbia was also included on these figures. The initial appearance of AIDS in the United States had three foci-the metropolitan areas of New York City, San Francisco, and Los Angeles. Prior to 1983, 67 percent of the AIDS victims in the country were confined to these 4 Colin Norman, Africa and Origins of AIDS, Science 230 (6 Dec. 1985): 1141. 5 Ronald C. Desrosiers, Origins of the Human AIDS Virus, Nature 319 (27 Feb. 1986): 728. 6 Desrosiers, footnote 5 above. This content downloaded from 157.55.39.135 on Sun, 03 Jul 2016 04:14:23 UTC All use subject to http://about.jstor.org/terms 458 THE GEOGRAPHICAL REVIEW

Sublethal malathion induced changes in the ovary of an air-breathing fish, Heteropneustes fossilis: a histological study

This paper describes effects of a sublethal (1.2 mg 1−1) organophosphate, malathion, on the ovary of an air breathing catfish, Heteropneustes fossilis. The study focuses on microscopic changes that occur on ovigerous lamellae, oocytes at different stages of development and the nucleus of the immature oocyte. Also, change in estrogen levels in blood serum is investigated. Clumping of cytoplasm appears after 24 h of exposure to malathion. Clumping intensified after 48 h. Degeneration in the follicular cells was also observed. After 72 h exposure the number of nucleoli increased, nuclear materials shrunk, oocytes became adhered. With 96 h of exposure, nuclear materials of all the oocytes shrunk to a smaller clump. The oocytes fused together, and follicular epithelium became loose and ruptured. A few atretic oocytes were visible. Radioimmunoassay of the estrogen level in blood serum after 72 h of exposure of malathion showed a reduction in the level. This study showed that the histopathological condition of the gonad is reflected in malfunctioning of the endocrine system and hormonal disbalance.