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Addictive substances

Ethyl alcohol – the most known depressant

All alcoholic beverages contain the same chemical – Ethyl alcohol, i.e. ethanol ${\text{C}}_{\text{2}}{\text{H}}_{\text{5}}\text{OH}\text{.}$ Consumed alcohol almost immediately gets into the blood – it is already absorbed in the mouth and penetrates very quickly through the gastrointestinal mucosa.

Alcoholic beverages have narcotic properties. The alcohol contained in them primarily attacks the nervous system and leads to poisoning of the body. As a result, the coordination of movement, speech, sensation and behaviour control is impaired. Consumption of alcohol for a long time causes permanent damage in the body and changes in the nervous system and other organs, such as the kidneys or liver.

The level (concentration) of alcohol in the blood is determined in per mils. The number of per mil (‰) indicates how many grams of alcohol is in one litre of blood tested.

The concentration of alcohol in the blood (determining the degree of intoxication) depends on the amount of ethanol consumed, body weight, sex, health status, and individual body characteristics. The lethal dose of alcohol for an adult is approximately 450–500 g of ethanol (approximately 1100g of vodka). Calculated per kilogram of body, it is about 6–8 g of alcohol for an adult and about 3 g for a child.

In the human body, ethanol undergoes metabolic processes. The human liver is able to oxidize 4–8 g alcohol/hour. Oxidation processes occur under the influence of enzymes, according to the scheme:

$\text{R–C}{\text{H}}_{\text{2}}\text{OH → R–CHO → R–COOH → C}{\text{O}}_{\text{2}}\text{+}{\text{H}}_{\text{2}}\text{O}$

Young organisms become particularly quick accustomed to alcohol, and its lack is felt as so‑called alcohol craving. People who abuse alcohol have learning difficulties because they suffer from memory impairment, problems with concentration and logical thinking. Systematic drinking of alcohol irreversibly damages the organs and tissues of the body, causing numerous diseases (liver cirrhosis, chronic inflammation of the pancreas, hypertension, heart rhythm disturbances, strokes, infertility or liver, oesophagus and larynx cancers). Frequent consumption of alcohol can lead to alcohol addiction (the World Health Organization recommends avoiding the term „alcoholism”, and instead recommends using the terms „alcohol addiction syndrome” or „alcohol addiction”).

Methyl alcohol (methanol) is more toxictoxic propertiestoxic than ethanol. Drinking it or absorbing its vapours through the respiratory tract shock the nervous system, causing blindness or even death. It was investigated that methyl alcohol is metabolized by humans at a rate 5 times lower than ethyl alcohol. After a single dose, its excretion through the kidneys and lungs lasts at least 4 days.

Methanol metabolism scheme:

$\text{C}{\text{H}}_{\text{3}}\text{–OH ⇆ HCHO ⇄ HCOOH}\stackrel{\text{very slow}}{\leftrightarrows }\text{C}{\text{O}}_{\text{2}}\text{+}{\text{H}}_{\text{2}}\text{O}$

Methanol metabolites (aldehyde and formic acid) directly damage cells, denature proteins, these also act on the nerves, especially the optic nerve. Toxicity therefore affects primarily the central nervous system, the optic nerve, as well as the kidneys, liver and heart. In the eye, apart from the optic nerve, retina and cornea are damaged. In addition, formic acid causes the formation of metabolic acidosis.

Nicotine – the most commonly used stimulant

The first cigarette is usually accompanied by choking, headaches, nausea and even vomiting. However, despite this, some people reach for a cigarette for the second and third time – until the body itself signals the need for nicotine, because it was gradually used to it. There is an addiction, called nicotine addiction, which is extremely difficult at this stage to fight. After inhaling tobacco smoke, a huge amount of poisonous chemicals enters the body through the respiratory system, including nicotine, hydrogen sulphide, ammonia, methanol, carbon monoxide and carcinogenic tar substances as well as radioactive isotopes.

Nicotine inhaled during smoking narrows the blood vessels of the smoker, which after a long time leads to heart disease and the entire cardiovascular system. The lungs necessary for human life become less efficient. The complexion is destroyed, the teeth turn yellow, and the breath becomes stale. A complex mixture of compounds present in tobacco and tobacco smoke also increases the risk of many dangerous diseases development, including all types of cancer. About how strong poison is nicotine, testifies, among others its use as an insecticide in gardening. The LD Indeks dolny 50₅₀ is about 1--1.5 mg/kg of body weight.

Task 1

Watch the movie to better understand effect of smoking cigarettes.

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Film przedstawia eksperyment, do którego zostało użytych czterysta papierosów. Obserwując eksperyment, można zwrócić uwagę, jak zmienia się kolor roztworu w naczyniu, do którego wpada dym papierosa. W podobny sposób dym dostaje się do układu oddechowego po każdym kolejnym papierosie. Roztwór ciemnieje, ponieważ dostaje się do niego po każdym następnym papierosie porcja (18 mg) papierosowej smoły. Po odparowaniu tej smoły zostaje w naczyniu bardzo dużo. Czterysta papierosów może jej dostarczyć płucom aż 7 i 2/10 grama. Dym papierosowy zawiera substancje rakotwórcze. Ponad 80% osób chorych na raka płuc to są palacze.

Film przedstawia eksperyment, do którego zostało użytych czterysta papierosów. Obserwując eksperyment, można zwrócić uwagę, jak zmienia się kolor roztworu w naczyniu, do którego wpada dym papierosa. W podobny sposób dym dostaje się do układu oddechowego po każdym kolejnym papierosie. Roztwór ciemnieje, ponieważ dostaje się do niego po każdym następnym papierosie porcja (18 mg) papierosowej smoły. Po odparowaniu tej smoły zostaje w naczyniu bardzo dużo. Czterysta papierosów może jej dostarczyć płucom aż 7 i 2/10 grama. Dym papierosowy zawiera substancje rakotwórcze. Ponad 80% osób chorych na raka płuc to są palacze.

Film dostępny na portalu epodreczniki.pl

Film przedstawia eksperyment, do którego zostało użytych czterysta papierosów. Obserwując eksperyment, można zwrócić uwagę, jak zmienia się kolor roztworu w naczyniu, do którego wpada dym papierosa. W podobny sposób dym dostaje się do układu oddechowego po każdym kolejnym papierosie. Roztwór ciemnieje, ponieważ dostaje się do niego po każdym następnym papierosie porcja (18 mg) papierosowej smoły. Po odparowaniu tej smoły zostaje w naczyniu bardzo dużo. Czterysta papierosów może jej dostarczyć płucom aż 7 i 2/10 grama. Dym papierosowy zawiera substancje rakotwórcze. Ponad 80% osób chorych na raka płuc to są palacze.

Drugs

Strong painkillers, and sometimes even drugs (such as morphine), are used by patients suffering from very painful diseases (e.g. cancer).

The drug user craves the effects these cause and needs regular and higher doses to get them. It is extremely difficult to quit the habit. Drugs change awareness and behaviour, causing depression, mental disorders and hallucinations; these are psychoactivepsychoactive substancespsychoactive.

Drug use results in irreversible changes in the psyche and the human body, causing permanent brain damage by substances considered to be drugs. General health deteriorates. Important vital functions, such as breathing or kidney work, are disturbed, which inevitably leads to death. The cause of these changes is permanent brain damage.

AIDS is particularly related to drug use.

There are many drugs commonly available (e.g. morphine, cocaine, amphetamine, LSD, mescaline, opium, heroin, hashish, marijuana, etc.), each in several forms (powder, pills, solution, joint).
Some drugs are obtained from plants (heroin, cocaine), others are synthesized (amphetamine, LSD).

Summary

• Chemical substances may affect the human body and cause the desired effect (medicines) and or act adversely - toxic (poisons).

• This is primarily determined by the dose of the substance and the way it penetrates the body (through the skin, respiratory system or digestive system). When using medication, it is very important to follow the doctor's instructions – take the right doses of the medicine and take it over a sufficiently long period of time.

• Stimulants are a group of substances that have no nutritional value, but are taken by people because of their stimulating effects on the nervous system. Long‑term administration can lead to addiction. Stimulants include, for example, alcohol, nicotine (from tobacco) and the most dangerous drugs and afterburners. Stimulants also include coffee, tea and energy drinks. All stimulants change (to a greater or lesser extent) the state of human consciousness.

Keywords

Poison, toxic properties

Glossary