bio-magnification

"Chemicals have replaced bacteria and viruses as the main threat to health. The diseases we're beginning to see as the major causes of death in the latter part of this century and into the 21st century are diseases of chemical origin."

 

Dick Irwin, toxicologist at Texas A&M Universities

 

BIO-MAGNIFICATION

 

Conservative pollutants are not metabolized (broken down inside an organism) and therefore when an organism containing a pollutant is eaten, the pollutants are simply passed on to the predator and accumulate in its tissues. By consuming many prey an organism may build up very high concentrations of the pollutant in its tissues. This process may continue up the food chain, leaving the top predator with very high and sometimes lethal concentrations of the pollutant. Organisms may ingest or absorb more than one pollutant at a time.  Two pollutants may interact to produce a toxic effect which is greater than the combined effect of the two pollutants simply added together i.e. one of the pollutants may increase the mortality caused by the other. This is called synergism.  High concentrations of lead, zinc and mercury are each capable of slightly reducing the growth rate of aquatic protozoa, but when acting together the overall effect is much higher.

 

Organic

Organochlorines are hydrophobic (water-hating) and show low solubility in water, but are readily soluble in fat (lipophilic).  Consequently, they will often accumulate in the fatty (adipose) tissue of an organism. In the past, organochlorines have been widely used as pesticides. They have two important characteristics:
1. They are chemically stable and remain active in the environment for many years.
2. They are fat-soluble and readily concentrate in adipose tissue. Whilst there, even high concentrations may cause little if any harm.
However, in times of  food shortage, fat reserves may be metabolized, releasing the pesticide into the blood of the organism. This may be fatal.

All pesticides must be considered potentially toxic to humans and animals. Exposure to some pesticides, particularly the organophosphates, destroys important enzymes in the nervous system. Repeated exposure may, without producing symptoms, progressively increase susceptibility to poisoning.The organophosphates are involved in more cases of occupational poisoning and deaths than any other single group of pesticides.

 

The symptoms of poisoning by organophosphates progress through several stages.The usual sequence of symptoms of mild poisoning is as follows: fatigue, headache, dizziness, numbness in the arms or legs, nausea and vomiting, excessive sweating and salivation, and abdominal cramps or diarrhea.In moderate poisoning, the symptoms listed for mild poisoning become more severe. Additional symptoms for moderate poisoning include inability to walk, generalized weakness, difficulty in talking, muscular twitches, and contraction of the pupil of the eye.

 

The symptoms for severe poisoning are unconsciousness, severe contraction of the pupil of the eye, muscular twitches, secretions from the mouth and nose, and respiratory difficulty. If victims of severe poisoning are not treated immediately, death will usually result.Illness is frequently delayed several hours, and an applicator may first become sick at home after supper. If symptoms begin more than 12 hours after the last known exposure to the pesticide, illness is probably due to some other cause.The carbamates likely to cause illness through occupational exposure act in the same way as the organophosphates, and produce the same type of poisoning symptoms.

 

The illness caused by carbamates is usually not as severe or as enduring, however, and they are generally considered safer than the highly toxic organophosphates.Pyrethrin is extracted from the flowers of chrysanthemum plants. Synthetic pyrethroids, which are chemically similar to pyrethrins, are manufactured in pesticide laboratories. Both of these insecticides are highly toxic to insects and fish but less toxic to humans than most insecticides. Pyrethrins and synthetic pyrethroids affect the central nervous system, and extremely high exposure results in convulsions, lack of coordination, and a tetanic-like condition. Because of their low level of toxicity, however, pyrethrins and synthetic pyrethroids usually cause only irritation to the skin and eyes.

 

Chlorinated Hydrocarbons

 

Only a few organochlorines have caused occupational poisoning. Several of them are regularly stored in the body tissues, however, and may accumulate in considerably higher concentrations in pesticide applicators than in the general population. Early symptoms of poisoning include headache, nausea, vomiting, general discomfort, and dizziness. With more severe poisoning, convulsions follow or may appear without these early warning symptoms. Coma may follow the convulsions. Excessive excitability and irritability are common symptoms.

 

The metallic pesticides that cause the most poisonings in the United States are those containing arsenic. Large single doses of most heavy metal pesticides cause vomiting and stomach pain. The exact nature of the symptoms varies with the metal, but in all cases the illness is chronic.

 

Cyanide

 

Cyanide is one of the fastest-acting poisons. Massive doses results in unconsciousness and death without warning. Smaller doses may result in the odor of bitter almonds on the breath, salivation, nausea, anxiety, confusion and dizziness. Illness may last one or more hours, terminating with unconsciousness, convulsions, and death from respiratory failure.

 

Anticoagulants

 

The injurious effects of anticoagulants are due to loss of blood, mainly into the body tissues. For example, the initial symptoms in chronic warfarin poisoning are back pain and abdominal pain.

 

Fluoroacetates

 

Poisoning from fluoroacetates (1080, for example), causes stimulation of the central nervous system resulting in convulsions and abnormal heart rhythm.

 

Dinitrophenols

 

The symptoms of poisoning by one or a few relatively large doses of the dinitrophenols (Elgetol, for example) include headache, nausea, gastric distress, restlessness, a sensation of heat, flushed skin, sweating, deep and rapid respiration, fast beating of the heart, fever, ashen color, collapse and coma.Acute poisoning with DNOC usually runs a rapid course. Death or almost complete recovery within 24 to 48 hours is the general rule.

 

Fumigants

 

Symptoms of excessive exposure to fumigants are similar to drunkenness (poor coordination, confusion, sleepiness and unconsciousness).

Methyl bromide is extremely dangerous because a toxic or even fatal dose can be absorbed before symptoms appear. Many fumigants can also cause severe chemical burns when trapped against the skin. Do not wear tight clothing or jewellry (even watches or rings) when using liquid fumigants.

 

Pyridyliums

 

Pyridylium herbicides (paraquat, for example) may be harmful if inhaled or absorbed through the skin and may be fatal if swallowed. Lung fibrosis can develop if paraquat is swallowed or inhaled. The symptoms of injury may be delayed. Prolonged skin contact will cause severe irritation.

 

Other concerns are

 

. Studies show that the growth of young birds can be stunted in areas where insecticides have been used heavily

 

. Developmental and behavioral effects in various animal species

 

. Associated with non-Hodgkin's lymphoma

 

. Reproductive and endocrine disruptions

 

. Associated with a cancer in dogs (canine malignant lymphoma)

 

. Increased number of abnormal sperm in exposed farmers

 

. Decreased fertility in male rats

 

why we do it

Once upon a time, there was a wise man who used to go to the ocean to do his writing. He had a habit of walking on the beach before he began his work.

One day, as he was walking along the shore, he looked down the beach and saw a human figure moving like a dancer. He smiled to himself at the thought of someone who would dance on the beach , and so he walked faster to catch up.

As he got closer, he noticed that the figure was that of a young man, and that what he was doing was not dancing at all. The young man was reaching down to the shore, picking up small objects, and throwing them into the ocean READ MORE

 

 

How we started

 

Whilst out walking with my dog in the early 1980's I found a small hedgehog stuck in a fence. He was too fat to go through and his prickles wouldn't’t let him go back.

He had been pushing so long in an attempt to free himself that the wire had cut into his body and his leg was bleeding where he had pushed and pushed against the ground. I had in my handbag a pair of pliers (no surprise to anyone who knows me) I cut the wire and removed the hedgehog READ MORE

 

volunteers

We are run totally by volunteers. Our volunteers are dedicated and come from a wide range of backgrounds and all bring something special to our team.

 

We are always looking for more volunteers to carry out some of the roles below.

If you have some spare time and would like to help us in some area please fill out our volunteers form and return it to info@harperaspreywildliferescue.co.uk. and we will be in contact with you.

As well as helping with animal care, there are other volunteering opportunities.

 

Maybe you could collect injured animals in your area when needed and bring them into us.

 

Perhaps you have experience in fundraising or PR and you can help raise awareness of our charity through local and national media?

 

Maybe you have strong administration skills.

If you think that you have the skills to help us then please complete the form on this page. Volunteers

 

 

We are sorry but we cannot take anyone under the age of 18.

 

education education education education education

 

As well as working on the front line we give talks and show our stunning wildlife to a variety of groups and schools - Wildlife Rocks Me Talks. We believe that a better understanding of these creatures will promote not only tolerance but a willingness to integrate them into our lives.

 

Children will become the custodians of our planet and we hope, through our talks, will have a better understanding of and take an interest in our wonderful wildlife as they take on that ultimate role.

 

We raise funds by donations, our newsletter, attending County Shows, Car boot sales, selling on eBay, Fairs, and our shop.

volunteers

We are run totally by volunteers. Our volunteers are dedicated and come from a wide range of backgrounds and all bring something special to our team.

 

We are always looking for more volunteers to carry out some of the roles below.Volunteers

 

 

Proof Read by Nicki