What Is Arsenic Poisoning?
Arsenic poisoning occurs when large amounts of arsenic—a naturally occurring element found in soil and groundwater—enter the body via ingestion, inhalation, or dermal exposure. It is both a public health hazard and a classic example of slow poisoning in forensic medicine.
It can be:
- Acute: Sudden exposure to a high dose
- Chronic: Long-term exposure to smaller doses (e.g., contaminated water)
Common Sources of Arsenic Exposure
- Contaminated drinking water (especially in parts of South Asia)
- Pesticides, herbicides
- Traditional medicines
- Industrial smelting, glass production
- Adulterated drugs or Ayurvedic formulations
How Arsenic Affects the Body
Arsenic interferes with cellular respiration by inhibiting pyruvate dehydrogenase. It also:
- Damages capillaries → hemorrhage
- Causes multi-organ dysfunction (liver, kidney, skin, nerves)
- Is highly carcinogenic with long-term exposure
Mnemonic Breakdown: HARMFul CASH
This visual mnemonic groups the key features of arsenic poisoning:
| Mnemonic | Clinical Feature |
|---|---|
| H | Hemorrhagic spots in mucosa |
| A | Addison-like disease |
| R | Raindrop pigmentation |
| M | Mees lines on nails |
| F | Fatal dose: 120–200 mg |
| C | Cholera-like diarrhea |
| A | Arsenic neuritis |
| S | Subendothelial petechial hemorrhages |
| H | Hyperkeratosis of palms and soles |
H – Hemorrhagic Spots in Mucosa
- Found on oral mucosa, GI lining, and conjunctiva
- Results from capillary fragility and endothelial damage
- May resemble bleeding disorders
A – Addison-like Disease
Arsenic mimics adrenal insufficiency symptoms:
- Hypotension
- Hyperpigmentation
- Fatigue
R – Raindrop Pigmentation
- Classic feature of chronic arsenic poisoning
- Skin shows diffuse brown hyperpigmented patches interspersed with depigmented spots
- Most visible on trunk and limbs
- Often misdiagnosed as eczema or fungal infection
M – Mees Lines on Nails
- Transverse white lines on fingernails
- Reflect arsenic-induced keratin matrix disruption
- Appear weeks after exposure → used in toxicological timelines
F – Fatal Dose and Toxic Range
- 120–200 mg of arsenic trioxide is considered fatal
- Causes cardiovascular collapse, multi-organ failure
- Can be absorbed via GI tract, lungs, and skin
C – Cholera-like Diarrhea
Watery, rice-water stools similar to Vibrio cholerae
Leads to:
- Severe dehydration
- Electrolyte imbalance
- Metabolic acidosis
A – Arsenic Neuritis
- Peripheral sensory-motor neuropathy
- Stocking-glove pattern of numbness and pain
- Chronic form leads to muscle wasting, foot drop
S – Subendothelial Petechial Hemorrhages
Seen in autopsy or severe acute cases
Causes:
- CNS symptoms (confusion, seizures)
- Skin rashes, purpura
H – Hyperkeratosis of Palms and Soles
- Thickening and scaling of skin
- Resembles tarsal corns or plantar warts
- Seen in chronic toxicity
- Considered a precancerous skin lesion
Diagnosis and Toxicology Testing
Confirmatory Tests:
- Urinary arsenic (best within 24–48 hours)
- Hair and nail arsenic (for chronic exposure)
- Blood arsenic (less reliable due to short half-life)
Other Tests:
- CBC, LFT, RFT
- ECG (to rule out QT prolongation)
- Nerve conduction studies
Treatment and Chelation Therapy
Immediate Steps:
- Remove from source of arsenic
- IV fluids and electrolyte replacement
- GI decontamination if early
Chelating Agents:
- Dimercaprol (BAL) – IM injections for acute poisoning
- DMSA (Succimer) – for milder or chronic toxicity
- Penicillamine – alternative for long-term management
Case Study: Chronic Arsenic Exposure in a Village
In a West Bengal village, a cluster of patients showed:
- Skin pigmentation changes
- Numbness in limbs
- Nail striping
Testing revealed arsenic contamination in groundwater. Patients responded well to clean water and DMSA.
Learning Point: Chronic poisoning may go unnoticed unless public health systems are proactive.
Forensic and Legal Aspects of Arsenic Poisoning
- Historically known as the “poison of kings” due to its tastelessness and delayed onset
- Can be used in homicide or suicide
- Poisoning must be reported to forensic authorities
- Nail and hair testing serve as forensic timelines
Prevention and Public Health Measures
- Regular testing of drinking water in high-risk regions
- Educating populations on safe water storage
- Using activated alumina or reverse osmosis filters
- Proper handling of industrial waste
- Regulating arsenic content in herbal and Ayurvedic products
Mnemonic Recap and Clinical Summary Table
Mnemonic: HARMFul CASH
| Letter | Clinical Feature |
|---|---|
| H | Hemorrhagic mucosa spots |
| A | Addison-like pigmentation & symptoms |
| R | Raindrop pigmentation |
| M | Mees lines on nails |
| F | Fatal dose: 120–200 mg |
| C | Cholera-like diarrhea |
| A | Arsenic neuritis |
| S | Subendothelial hemorrhages |
| H | Hyperkeratosis of palms/soles |
FAQs on Arsenic Poisoning
Q1: Can arsenic poisoning be reversed?
A: Acute effects can be managed with chelating agents and supportive therapy. Chronic skin changes may be permanent.
Q2: What is the best test for chronic arsenic exposure?
A: Hair and nail analysis, as they retain arsenic for weeks/months.
Q3: Can you die from touching arsenic?
A: Unlikely, unless absorbed in large quantities over time or if ingested.
Q4: Is arsenic still used today?
A: Yes—in very controlled doses in semiconductors, wood preservatives, and historically in homeopathy.
Q5: What foods contain arsenic?
A: Small amounts may be found in rice, seafood, and groundwater crops, but within regulated safe limits.
