Introduction

 

Kingdom: Animalia

Phylum: Chordata

Class: Reptilia

Family: Viperidae

Subfamily: Crotalinae

Genus: Crotalus

Species: C.atrox

 

• Diamondback rattlesnake may refer to western diamondback rattlesnake,  Eastern diamondback rattlesnake and Red diamond rattlesnake.
• This blog is about Western diamondback rattlesnake.
• It is likely responsible for the majority of snakebite fatalities in northern Mexico and the greatest number of snakebites in the U.S.
• Size – 3 to 7 feet long
• Life span – approximately 15 to 20 years
• A bite from a fully-grown western diamondback rattlesnake can result in severe envenomation and death, in the absence of adequate treatment, since the rattlesnake venom is a potent mix of hemotoxins, myotoxins, and cytotoxins

Read more

Common names

• Western diamond-backed rattlesnake
• Adobe snake
• Arizona diamond rattlesnake
• Coon tail
• Desert diamond rattlesnake
• Buzz tail
• Texas rattler.

Identifying Features

 

• It is a heavy-bodied snake with a triangular-shaped head.
• There are 2 dark diagonal lines on each side of its face running from eyes to its jaws.
• It has a dark diamond-shaped pattern along its back.
• The tail has black and white bands just above the rattles.

Read More

Adaptations

Western diamondbacks are pit vipers, which means that they have a heat-sensing pit located behind each nostril that can detect differences in temperature. The heat given off by an animal is detected by the snake helping it to determine predator from prey.

Habitat

• It can be found living in deserts, forests, rocky hillsides, grassy plains, and areas along the coast.
• It lives in elevations from below sea level up to 6500 feet(2000m).

Symptoms and Signs of bite

Bites are painful

• bleeding
• difficulty breathing
• blurred vision
• eyelid drooping
• low blood pressure
• nausea and vomiting
• numbness
• paralysis
• rapid pulse
• change in skin color
• swelling
• tingling
• tissue damage
• thirst
• tiredness
• weakness

Some of the systemic signs and symptoms may include:

• Bleeding disorder due to:
  • Decreased blood platelets or thrombocytopenia
  • Destruction of red blood cells or hemolysis
• In severe cases, internal hemorrhaging including:
  • Blood in urine
  • Bleeding from recent wounds
  • Mucosal bleeding – from nose, ears, eye, gastrointestinal tract, etc.
  • Anemia due to spontaneous bleeding
• Acute kidney injury or kidney failure
• Neurological symptoms, in some cases

What NOT to do

• allowing the person who has been bitten to become over-exerted
• applying a tourniquet
• applying a cold compress
• cutting into the bite with a knife or razor
• trying to suck out the venom
• giving any stimulants or pain medication unless told to by a doctor
• giving a person who has been bitten anything to eat or drink
• raising the site of the bite above the person’s heart

Read more

Diagnosis

• Complete physical examination with a comprehensive evaluation of medical history.
• Assessment of the signs and symptoms
• Blood tests that may include: (many of these tests are repeated over the course of treatment)
  • Complete blood count (CBC) with differential and platelet count
  • White blood cell count
  • Hematocrit blood test: Hematocrit is the proportion of blood that is made up of red blood cells
  • Prothrombin time (PT) and partial thromboplastin time (PTT) tests
  • Fibrinogen blood test
  • Lactate dehydrogenase (LDH) test
  • Serum electrolytes including blood urea nitrogen (BUN) and creatinine levels
  • Arterial blood gas

• Urine test to test for free protein, myoglobin, and hemoglobin levels
• Electrocardiogram or ECG, to check for arrhythmias and hyperkalemia
• Kidney function test
• Liver function test
• Nerve conduction studies and neurological evaluation, if necessary

Treatment

• Administration of IV fluids to keep the patient well-hydrated; pain medication
• Administration of anti-snake venom (ASV) to neutralize the venom through slow intravenous injection or infusion method, especially when severe symptoms are noted
• Address any signs of an early allergic reaction: A close observation of the patient is necessary for a minimum of 60 minutes immediately following antivenom administration, to detect early allergic reactions, if any
• Periodic blood and urine tests are undertaken for 12-24 hours or more
• Tetanus vaccination is required
• The patient is generally admitted and placed in an ICU setting and monitored for at least a day following the abatement of symptoms; the patient has to be rested and kept warm
• If necessary, blood and plasma transfusions for severe cases
• Intubation and respiratory support
• Providing life support, such as ventilation assistance and treatment for shock, for those with severe symptoms leading to potential organ failure
• Medications to control blood pressure
• Peritoneal dialysis for acute kidney failure
• Pressure management of the affected limb for compartment syndrome
• Rehabilitation of the affected limb through physical therapy

Prevention

• Wear boots and long pants when hiking to help block rattlesnake venom.
• Stay on trails when hiking, away from the underbrush and tall weeds.
• Do not touch or disturb a snake, even if it appears dead.
• Always look for concealed snakes before picking up rocks, sticks or firewood
• Never hike alone in remote areas. Always have someone with you who can assist in an emergency.

Rattlesnake facts: this video explains how to identify rattlesnake, about its habitat, reproduction, characteristics features.

References

1. https://en.wikipedia.org/wiki/Western_diamondback_rattlesnake
2. https://www.healthline.com/health/rattlesnake-bite#treatment
3. Klauber LM. (1997). Rattlesnakes: Their Habitats, Life Histories, and Influence on Mankind. 2nd ed. First published in 1956, 1972. University of California Press, Berkeley.
4. McDiarmid RW, Campbell JA, Touré T. (1999). Snake Species of the World: A Taxonomic and Geographic Reference, vol. 1. Herpetologists’ League
5. Wright AH, Wright AA. (1957). Handbook of Snakes. Comstock Publishing Associates. (7th printing, 1985).

 

 

Introduction

• Ethanol is a volatile, flammable, colorless liquid with a slight characteristic odor.
• Chemical formula – C₂H₆O
• Is the principal active ingredient found in alcoholic drinks.
• Ethanol is considered a universal solvent, as its molecular structure allows for the dissolving of both polar, hydrophilic and non-polar, hydrophobic

 

figure 1

Synonyms

Absolute alcohol
alcohol
cologne spirit
drinking alcohol
ethyl alcohol

ethyl hydrate
ethyl hydroxide
ethylol
grain alcohol
hydroxyethane
methylcarbino

Sources

Ethanol can be fermented from many sources of starch, including:

• Corn
• Wheat
• Grain sorghum
• Barley
• Potatoes
• Sugar cane
• Sweet sorghum

Structures

figure 2

History

• Started being used in the U.S as lamp fuel in 1840.
• In 1908, Ford Model T’s could be run on ethanol
• When prohibition started in 1920, ethanol fuel sellers were suspected of selling alcohol, so they stopped the production.
• The fermentation of sugar into ethanol is one of the earliest organic reactions that man learned to carry out and the history of man-made ethanol is very long.
• Read More:  https://www.eia.gov/energyexplained/biofuels/ethanol.php

 

Uses

figure 3

Medical :

• Antiseptic
• Antidote
• Medicinal solvent
• Pharmacology

Recreational

Fuel :

• Engine fuel
• Rocket fuel
• Household heating

Feedstock

Solvent

Drinks

Mechanism of action of alcohol

• Is a CNS depressants
• Acute alcohol causes:

–Enhancement the effect of GABA( inhibitory neurotransmitter) on its GABA receptors in brain leading to CNS depression

-Inhibition of glutamate action (excitatory neurotransmitter) on NMDA receptors leading to disruption in memory, consciousness, alterness.

figure 4

Read more: https://www.sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceutical-science/ethanol

Metabolism

The primary site of ethanol metabolism is the liver. However, other organs are also able to metabolize alcohol, but to a lesser degree. These include the kidneys, lungs, and digestive organs.

Read more: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3484320/

Toxicokinetics

Absporbtion

• GI tract (small intestine) when ingested
• Lungs when inhaled
• Sometimes absorbed by the skin.

Distribution

• Ethanol is distributed equally throughout the body depending on:
  • the amount of water in that area.
  • blood flow to that area
  • tissue mass

Metabolism:

• Via liver

Elimination:

• Typically via breath, breast milk, urine, sweat, saliva, feces.

Symptoms

figure 5

Alcohol poisoning signs and symptoms include:

• Confusion
• Vomiting
• Seizures
• Slow breathing (less than eight breaths a minute)
• Irregular breathing (a gap of more than 10 seconds between breaths)
• Blue-tinged skin or pale skin
• Low body temperature (hypothermia)
• Passing out (unconsciousness) and can’t be awakened

Treatments

• Careful monitoring
• Prevention of breathing or choking problems
• Oxygen therapy
• Fluids given through a vein (intravenously) to prevent dehydration
• Use of vitamins and glucose to help prevent serious complications of alcohol poisoning

Complications

Severe complications can result from alcohol poisoning, including:

• • Choking
  • Stopping breathing (asphyxiation)
  • Severe dehydration
  • Seizures
  • Hypothermia
  • Irregular heartbeat
  • Brain damage
  • Death

Dangerous myths

You can’t reverse the effects of alcohol poisoning, and you could actually make things worse through some actions. Here’s what doesn’t work:

• • • Sleeping it off — you can lose consciousness while asleep
    • Black coffee or caffeine ― this does not counteract the effects of alcohol poisoning
    • A cold shower — the shock of cold can cause a loss of consciousness
    • Walking it off ― this does not increase the speed at which alcohol leaves your body

Prevention

To avoid alcohol poisoning:

• Drink alcohol in moderation, if at all
• Don’t drink on an empty stomach
• Communicate with your teens
• Store products safely
• Get follow-up care

References

1. National Center for Biotechnology Information. PubChem Database. Ethanol, CID=702, https://pubchem.ncbi.nlm.nih.gov/compound/Ethanol (accessed on July 7, 2020)
2. https://en.wikipedia.org/wiki/Ethanol
3.  “Ethanol – Compound Summary”. The PubChem Project. USA: National Center for Biotechnology Information.
4. figure 1, 2: https://www.nutrientsreview.com/wp-content/uploads/2015/10/Ethanol-structure.jpg
5. figure 3;<https://sites.google.com/site/wikilabblog/li>
6. figure 4 ;<https://www.frontiersin.org/articles/183708/li>
7. figure 5 ;<https://www.evergreendrugrehab.com/blog/alcohol-poisoning-symptoms-risks-prevention//li>

Fig-1

INTRODUCTION

• Atomic number: 33
• Atomic symbol: As
• Atomic weight: 74.92160
• Density: 5.776 grams per cubic centimeter
• Phase at room temperature: solid
• Melting point: 1,502.6 degrees Fahrenheit (817 degrees Celsius)
• Boiling point: 1,117.4 F (603 C)
• Number of isotopes: 33; 23 whose half-lives are known; 1 stable
• Most common isotopes: As-75 (100 percent natural abundance)

Fig-2

• An arsenic atom has 33 electrons and 33 protons with five valence electrons (those that can participate in forming chemical bonds with other electrons) in its outer shell.

  History

• Arsenic was used as a healing agent after Greek physicians such as Hippocrates and Galen popularised its use.

• Arsenic compounds became available as solutions, tablets, pastes, and injectable forms. Fowler’s solution, a 1% arsenic trioxide preparation, was widely used during the 19th century.

• As recently as 1958, the British Pharmaceutical and Therapeutic Products handbook edited by Martindale, listed the indications for Fowler’s solution as leukemia, skin conditions (psoriasis, dermatitis herpetiformis, and eczema), stomatitis and gingivitis in infants, and Vincent’s angina. Fowler’s solution was also prescribed as a health tonic.

• Chronic arsenic intoxication from the long term use of Fowler’s solution caused haemangiosarcoma, angiosarcomas of the liver, and nasopharyngeal carcinoma.

• Arsenic was the primary treatment for syphilis until World War II. Arsphenamine (neoarsphenamine), a light yellow compound containing 30% arsenic was used intravenously to treat syphilis, yaws, and some protozoan infections

Sources of exposure

• Arsenic is a natural component of the earth’s crust and is widely distributed throughout the environment in the air, water, and land.
• It can exist in inorganic or organic form, inorganic form being generally considered more toxic.
• About one-third of the arsenic in the atmosphere comes from natural sources, such as volcanoes, and the rest comes from man-made sources.
• Industrial processes such as mining, smelting, and coal-fired power plants all contribute to the presence of arsenic in air, water, and soil.
• High levels of arsenic can be found in drinking water

Fig-3

• Arsenic is found in the following foods: 
  • Rice 
  • Cereal 
  • Chicken 
  • Mushrooms
  • Seafood 

Fig-4

• Pressure-treated woods

Fig-5

Arsenic in food

Watch an interesting video about Arsenic in food.

While eating lunch, three students begin to wonder about the safety of eating foods that contain arsenic. Through their research, the students will discover where arsenic is found, how it is used, and its effects on human health.

Mechanism

Inorganic :

• Arsenate – exists in the +5 oxidation state.
• Arsenite- exists in +3 oxidation state.

Organic As- methylated

• Monomethylarsonous acid (MMA3)
• Dimethylarsinous acid (DMA3)

Arsenic toxicity and potential mechanisms of action

• The absorbed arsenic undergoes hepatic biomethylation to form monomethylarsonic acid and dimethylarsinic acid that are less toxic but not completely innocuous. About 50% of the ingested dose may be eliminated in the urine in three to five days. Dimethylarsinic acid is the dominant urinary metabolite (60%–70%) compared with monomethylarsonic acid. A small amount of inorganic arsenic is also excreted unchanged. After acute poisoning, electrothermal atomic absorption spectrometry studies show that the highest concentration of arsenic is in the kidneys and liver.

 

• In chronic arsenic ingestion, arsenic accumulates in the liver, kidneys, heart, and lungs and smaller amounts in the muscles, nervous system, gastrointestinal tract, and spleen. Though most arsenic is cleared from these sites, residual amounts remain in the keratin-rich tissues, nails, hair, and skin. After about two weeks of ingestion, arsenic is deposited in the hair and nails

Arsenic Metabolism

 

 

 

 

 

 

 

 

 

 

 

Uses

• ‘Poison of Kings’
• Arsenic is mostly used in compounds. A much smaller amount of the element itself is used in alloys. For example, certain parts of lead storage batteries used in cars and trucks contain alloys of lead and arsenic.
• Arsenic has also been used to make a lead shot in the past. The amount of arsenic used in these applications is likely to continue to decrease. It is too easy for arsenic to get into the environment from such applications.
• Minute amounts of arsenic are used in the electronics industry. It is added to germanium and silicon to make transistors. A compound of arsenic, gallium arsenide (GaAs), is also used to make light-emitting diodes (LEDs). LEDs produce the lighted numbers in hand-held calculators, clocks, watches, and a number of other electronic devices.
• Medical uses- syphilis, psoriasis

TOXICITY

Health effects: Signs and Symptoms

Inorganic arsenic is a confirmed carcinogen.

Acute effects:

•  vomiting
• abdominal pain
• diarrhea
• numbness
•  tingling of the extremities
• muscle cramping
• death (in extreme cases)

Long-term effects:

• pigmentation changes
• skin lesions
•  hard patches on the palms and soles of the feet (hyperkeratosis)
• bladder cancer
• lung cancer

Other effects:

• developmental effects
• diabetes
• pulmonary disease
• cardiovascular disease

Diagnosis

Pathological testing:

• blood
• hair
• urine
• fingernail samples

Urine tests should be done within 1-2 days of the initial exposure.

Tests on hair and fingernails can determine the level of arsenic exposure over the period of up to 12 months.

Chronic exposure levels between 0.1 to 0.5mg/kg

Acute toxicity has a range of 1 to 3mg/kg.

Treatment

• removing clothes that could be contaminated with arsenic
• thoroughly washing and rinsing affected skin
• blood transfusions
• taking heart medication in cases where the heart starts failing
• using mineral supplements that lower the risk of potentially fatal heart rhythm problems
• observing kidney function
• bowel irrigation

this video is a graphical representation of symptoms, complications, and treatment of arsenic poisoning.

Differential Diagnosis

Acute arsenic toxicity presents similarly to many gastrointestinal conditions including:

• Guillain-Barre
• Campylobacter
• Shigella
• Salmonella
• Escherichia coli
• Clostridium difficile
• Bacillus cereus
• Vibrio cholerae
• Rotavirus
• Giardia lamblia
• Cryptosporidium
• Entamoeba histolytica

Prevention

• households having arsenic removal systems
• testing the water for traces of arsenic
• taking care when harvesting rainwater
• well depth: the deeper a well is dug, the less arsenic in water.
• AWARENESS program about the harmful effects.

References:

1. 1. https://www.who.int/news-room/fact-sheets/detail/arsenic
   2. https://en.wikipedia.org/wiki/Arsenic_poisoning
   3. Hughes MF, Beck BD, Chen Y, Lewis AS, Thomas DJArsenic exposure and toxicology: a historical perspective
      Toxicol Sci, 123 (2011), pp. 305-332
   4. Fig-1:https://encrypted-tbn0.gstatic.com/images?q=tbn%3AANd9GcSz0c0_IiDMG0I222sYH0onmaVb_nkTtj8ZNiYDx4wrGXwCKOSM&usqp=CAU
   5. Fig-2:https://encrypted-tbn0.gstatic.com/images?q=tbn%3AANd9GcQcCgUGuwQWc_LZ-AL7QdSKi6uYoq_weTO1i1IGlaAqclrhUuzX&usqp=CAU
   6. Fig-3:https://encrypted-tbn0.gstatic.com/images?q=tbn%3AANd9GcS775EBJzXwOl5cBCu6rmgBgFvm3FkGMSx1EZ1WOZurr53DlYTd&usqp=CAU
   7. Fig-4:https://encrypted-tbn0.gstatic.com/images?q=tbn%3AANd9GcTm6uX3u9qET0ytLHnO_QPCBW8nO1ypkQXCo0rd6i0ZRIffR4Tu&usqp=CAU
   8. Fig-5:https://contentgrid.homedepot-static.com/hdus/en_US/DTCCOMNEW/Articles/benefits-of-pressure-treated-wood-section-1.jpg”>benefits-of-pressure-treated-wood-section-1.jpg
   9. Fig-6:https://encrypted-tbn0.gstatic.com/images?q=tbn%3AANd9GcQuWzhpGuHn24xKAAMRTR2-dKzWRi72WmFXsiqSNIPlcTlkm0IE&usqp=CAU

Introduction

• Chlorothalonil is an organic compound used as a broad spectrum , non-systemic fungicide also used as pesticides , wood protect ,mold controller, acaricids.
• Mostly used to control fungi that affects agro crops.
• Products containing Chlorothalonil are sold under the names Echo , Bravo, Daconil.
• Its one of the top 3  fungicide in the USA
• First registered for use in 1997.
• Read more

Properties

Molecular Formula	C8Cl4N2
Molecular Mass	265.90 g·mol−1
Appearance	white crystalline solid
Desnsity	1.8 g cm−3, solid
IUPAC Name	2,4,5,6-Tetrachlorobenzene-1,3-dicarbonitrile
Synonyms	2,4,5,6-Tetrachloroisophthalonitrile Bravo Daconil Tetrachloroisophthalonitrile Celeste Bronco Agronil Aminil

 

How does Chlorothalonil work 

The video explains the mode of action of chlorothalonil.

Chlorothalonil deactivates glutathione actions.

 

Toxicology Effects

Acute Toxicity

• Eye irritant
• Skin irritant
• Loss of muscle coordination
• Rapid breathing
• Bleeding nose
• Hyperactivity

Chronic Toxicity

• Kidney damage and tumors
• Read more

Is Chlorothalonil safe !

• Always follow label instructions.
• Wear personal protective equipments
• Avoid risk of inhalation, ingestion, and coming in contact with the skin

 

 

Metabolism of Chlorothalonil following Oral administration to Rats

Clinical cases

• Only few cases have been reported of adverse effects in humans.
• Contact dermatitis is the most frequent diagnosis.

References:

1.Andre, J. C., et al. (1991a). “Comparison of the Effects of Dose Level and Vehicle on the Dermal Absorption of ¹⁴C-Chlorothalonil by Male Rats

2. “Chlorothalonil”. Pubchem

4.  PESTICIDE USE IN U.S. CROP PRODUCTION: 1997 Archived 10 December 2006 at the Wayback Machine National Center for Food and Agricultural Policy, 1997