Horse and Cart
Once the wheel had been discovered, the “horse and cart” soon followed. For centuries this was the best way in which to transport people and goods overland. With a harnessed horse walking while pulling a cart, it was a little easier. Better than walking yourself or pushing a small cart. It was also a little quicker.

Alternative - Horse
But the “horse and cart” had a number of limitations. The volume of goods which could be loaded onto a cart did not only depend on the cart. The number of horses which could be harnessed was also a limiting factor.
Sometimes an alternative to the horse was the solution. For transporting a heavier load, stronger animals, such as oxen, could replace the horses. A disadvantage with this, however, was that the journey progressed a little more slowly.
Faster animals to shorten the journey time have never really proved to be successful. Hares are too small and gazelles cannot be harnessed.
One of the most important limitations of the “horse and cart” was ultimately that it was not possible to travel faster than a horse could gallop. The need to be able to transport more and faster, whether people or goods, remained. No alternative could be found to the horse, which provided the strength and the speed, to solve the problem.

Alternative - Cart
Leonardo da Vinci was probably one of the first who in 1478 realised that the problem was not so much to find a better horse but another way in which to make the cart move. The solution was to drive the wheels of the cart with a wind-up spring such as we find in clocks or in children’s toys. It worked. But unfortunately only over a short distance, not further than a few metres.
Da Vinci’s solution was not to look at the horse but at the cart; the cart which, after all, could not be ignored. The idea came from approaching the problem in an alternative way.

Solution - Technology
However it took a few more centuries before the first steam carts appeared, which proved, however, not to be very successful because they were too heavy and too cumbersome. Only after the discovery of the combustion engine could the automobile, as we now know it, be developed. That was the end of the commercial use of the “horse and cart” in the western world.
Da Vinci’s cart was made of wood and the spring was made of iron. It lasted until science and technology had developed the materials necessary for the engines and other parts such as brakes and chassis, etc.

Conclusion
What started as looking for an alternative to the horse which was faster and stronger was solved by looking for an alternative to the cart. The solution could only be applied in practice after science and technology had developed far enough to implement the concept in practice.


Substances
Everyone expects that the air we breathe, the water we drink, the food we eat and the products we use are safe.
Not everyone is aware of the fact that today it is not possible to guarantee this safety without in one way or another making use of experimental animals.

Safety
Very briefly, assessment of the safety of substances involves a process with a number of steps which lead to a decision. Animals are exposed to the substances to be tested. Many things are measured in the animals, in the blood and urine. The results are interpreted. The dose which does not cause any harmful effects in the experimental animals is determined and divided by a large safety factor and so the dose which is considered to be safe for man is established.

Animal Testing
Animal testing is controversial. Some people are against it in principle. Many really do not want it. It is probable that if safety could be guaranteed without experimental animals, virtually everyone would be relieved.
In recent years a great deal has been achieved in the area of reducing and refining the use of experimental animals for the sake of human safety. In terms of finding a replacement, progress has been disappointing.

ASAT
ASAT - Assuring Safety without Animal Testing - aims to assess the health risk for man by examining the processes which cause harm and disease in man. Precisely the harm and disease that we want to prevent. ASAT makes use of new developments in science and technology. Through this it is possible to model and study biological processes and effects of substances in a way which, only a few years ago, was still unthinkable.
ASAT bases the assessment of the health risk on data from these models, which represent the relevant processes for this in man. This offers the prospect of data from animal experiments becoming redundant.

Solution - Cooperation
That stage has not yet been reached. It can only be reached if research groups in many countries contribute to the development of ASAT. This is not only necessary because it involves a sizeable amount of work but also because if groups from many countries cooperate, acceptance will be easier. The ASAT Innovation Programme that SenterNovem is carrying out on behalf of the Ministry of Health, Welfare and Sport is an important contribution of this kind.

Conclusion
What started as looking for an alternative to the experimental animal has led to an approach based on an alternative to the risk assessment of substances; an approach which offers the prospect of experimental animals becoming redundant.