Geology Essay, Research Paper

Physical changes in the land, soil, water, and air,

associated with industrialization directly and indirectly

affect the biological environment. Direct impacts include

deaths of plants, animals, or people, caused by mining

activity or contact with toxic soil or water from mines.

Indirect impacts include changes in nutrient cycling, total

biomass, species diversity, and eco-system stability due to

alterations in groundwater or surface water availability or

quality.

Water resources are particularly vulnerable to

degradation even if drainage is controlled and sediment

pollution reduced. Surface drainage is often altered at

mine sites, and run off from precipitation may infiltrate

waste material, leaching out trace elements and minerals.

Trace elements leached from mining wastes and concentrated

in water, soil, or plants may be toxic, causing diseases in

people and other animals who drink the water, eat the

plants, or use the soil. These potentially harmful trace

elements include cadmium, cobalt, copper, lead, iron,

molybdenum, zinc, and others.

Groundwater may also be polluted by mining operations

when waste comes into contact with slow-moving subsurface

waters. Surface-water infiltration or groundwater movement

through mining waste piles causes leaching of sulfide

materials that may pollute groundwater. The polluted

groundwater may eventually seep into streams to pollute

surface water. Groundwater problems are particularly

troublesome because reclamation of polluted groundwater is

very difficult and expensive.

An example of an area where trace elements have

affected a large part of the population is in Japan. An

increased amount of cadmium was released into the Zintsu

River Basin near the end of World War I. At this time the

Japanese industrial complex was damaged and good

industrial-waste disposal practices were largely ignored.

Mining operations for cadmium dumped mining wastes into

rivers. The cadmium influx occurred in estuarine waters and

in sediments after the intake of industrial wastes.

Farmers then used this contaminated water downstream

for domestic and agricultural purposes. This intake of

cadmium by human beings caused a chronic disease within the

Japanese population known as Itai-Itai. The name Itai-Itai

suits the disease because it is Japanese for ouch-ouch.

Itai-Itai is painful and crippling. It attacks the bones

causing them to become so thin and brittle that they break

easily.

Many solutions and experiments have been tried to find

reason and absolution of cadmium influx, but none has given

us a perfect resolution of the cause. Such experiments as

studying the bones and tissue of victims were quite

revealing. The bones and tissue were found to contain large

concentrations of zinc, lead, and cadmium. The study of

rats showed scientists interesting results. When rats were

fed 100ppm of cadmium they lost about 3 percent of their

total bone tissue. Rats fed amounts of cadmium plus other

trace elements such as lead copper and zinc lost about 33

percent of their total bone tissue.

Cadmium in seafood is another problem in Japan so

scientists were not surprised when they found out that

cadmium has deleterious effects on most, if not all, marine

species tested. Histopathological effects of cadmium have

been studied in two species of marine finfish. However, no

scientist has reported histopathological effects in any

invertebrates. Invertebrates are more sensitive to the

metal than are finfish. There are few reports on the rates

of accumulation of cadmium in marine species, and the only

investigations we are aware of are studies on the flux of

cadmium through mussels, shrimp, and euphausids. This lack

of information caused us to undertake the present study to :

(1) determine rates of accumulation and localization of

cadmium in tissues of shrimp; (2) describe the histological

effects of cadmium in shrimp; and (3) compare the

accumulation of cadmium in shrimp from meta incorporated in

food with that of cadmium administered directly in water.

Measurement of heavy-metal concentrations in Japan?s

Zintsu River Basin showed that although the water samples

generally contained less than 1 ppm cadmium and 50 ppm zinc,

these metals are selectively concentrated in the sediment

and even more highly concentrated in plants. One set of

data for five samples shows an average of 6 ppm cadmium in

polluted soils. In plant roots, this average increased to

1250, and in the harvested rice it was 125 ppm.

As of late scientists have been putting their energy

and time into research more than activating ways to quickly

and efficiently solve the problem. Some structures like

specially constructed ponds have been made to collect

polluted run off from mines have been made and do help, but

they cannot be expected to eliminate all problems.

Groundwater problems are particularly troublesome because

reclamation of polluted groundwater is very difficult and

expensive. So, until scientists have fully researched the

effect of trace elements in our geologic planet our society

will just have to look towards the future.