Heredity(遗传) is not the only thing that influences our color. Where we live and how we live after we are born are important too. For instance, our genes influence how fat or thin we are. But our weight depends mainly upon how much we eat and how much exercise we get. In the same way, our skin color depends to a large extent upon how much sunshine we get.

When summer arrives and light-colored people go to the beaches, some will tan darkly, some will tan lightly and few will not tan at all. Each one has inherited a different ability to tan, but the differences do not appear until the conditions are right. An outdoor man will soon become pale if he changes to an indoor job, while a desk clerk will take on tan after a short vacation in the sun.

Sometimes people decide that being tanned is better than being pale. Sometimes they decide the opposite.

Centuries ago, most of the people in Europe were peasants and they had to work in the fields all day. Noblemen, on the other hand, did not have to work. They stayed indoors and remained pale. You could always tell a nobleman from a peasant because a peasant had a tan. As a result, a shin so pale that the veins (血管) showed was considered a mark of great beauty.

During the Industrial Revolution things changed. Farmers left their fields and went to work in factories, mines and mills. Working for long hours in dimly-lit factories and mines made their skins pale. Wealthy people, however, could afford to travel so sunny countries. They had the leisure to lie around on the beaches and get tan. Having a tan became a sign of wealth.

In Western Europe and North America pale skin is no longer desirable. Instead of bleaching themselves white with lemon juice, many women spend their time under a sun-lamp. The desire for a quick tan has led to the invention of pills and lotions(涂剂) that darken the skin artificially without exposure to sunlight. These pills and lotions can be bought by anyone at any drugstore. A rich man can spend hundreds of dollars on a vacation in the sunny West Indies and get his suntan there. But his lowest-paid clerk can have what looks like the same tan out of a bottle for a few cents.

So there are three answers to the question “Where does our color come from?” It comes from the genes we inherit. It comes from the conditions in which we live. And it can come from a bottle that we buy at the drugstore on the corner of the street.

Some years ago industries had more f    50     than they have now, and they did not need to be as careful as they must today. They did not need to worry a lot about the safety of the new products that they developed. They did not have to pay much attention to the health and safety of the people who worked for them. Often new products were dangerous for the people who used them; often conditions in the work place had very bad effects on the health of the workers.

Of course sometimes there were real d    51     which attracted the attention of governments and which showed the need for changes. Also scientists who were doing research into the health of workers sometimes produced information that governments could not ignore. At such times, there were inquiries into the c    52     of the disasters or the problems. New safety rules were often i    53     as a result of these inquiries; however, the new rules came too late to protect the people who died or who became seriously ill.

Today many governments have special departments that protect customers and workers. In the U.S., for example, there is a department that tests new airplanes and gives w    54     about possible problems. It also makes the rules that aircraft producers must follow. Another department controls the foods and drugs that companies sell. A t    55     department looks at the places where people work, and then reports any companies that are breaking the laws which protect the health and safety of workers. Of course, new government departments and new laws cannot p    56     every accident or illness, but they are having some good results. Our work places are safer and cleaner than before. The planes and cars that we use for travel are better. Producers are thinking more about the safety and health of the people who buy and use their products.

Across the world, 1.1 billion people have no access to clean drinking water. More than 2.5 billion people lack basic sanitation. The combination proves deadly. Each year, diseases related to inadequate water and sanitation kill between 2 and 5 million people and cause an estimated 80 percent of all sicknesses in the developing world. Safe drinking water is a precondition for health and the fight against child death rate, inequality between men and women, and poverty.

Consider these facts:

●The average distance that women in Africa and Asia walk to collect water is 6 kilometers.

●Only 58 percent of children in sub-Saharan Africa are drinking safe water, and only 37 percent of childrenin South Asia have access to even a basic toilet.

●Each year in India alone, 73 million working days are lost to water-borne diseases.

Here are three ways you can help:

(1) Write Congress

Current U. S. foreign aid for drinking water and sanitation budgets only one dollar per year per American citizen. Few members of Congress have ever received a letter from voters about clean drinking water abroad.

(2) Sponsor a project with a faith-based organization

Many U.S. religious groups already sponsor water and sanitation projects, working with partner organizationsabroad. Simply putting a single project by a U.S. organization can make safe water a reality for thousands of people.

(3) Support nonprofit water organizations

Numerous U.S.-based nonprofits work skillfully abroad in community-led projects related to drinking water and sanitation. Like the sample of non-profits noted as follows, some organizations are large, other small-scale, some operate worldwide, others are devoted to certain areas in Africa, Asia, or Latin America. Support them generously.