Cosmetic Preservation and Visual Cortex Health

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What category is assigned to substances that are labeled 'strong corrosive' according to EU regulations?

Category 2

Category 1A (correct)

Category 1C

Category 1B

Which of the following test methods is NOT mentioned as an internationally accepted method for skin corrosion or irritation testing?

Transcutaneous Electrical Resistance test

Reconstructed human skin models

In vitro Human Tear Fluid test (correct)

In vivo Draize rabbit test

Which aspect of the Corrosive materials pertains to the Transcutaneous Electrical Resistance (TER) test?

It predicts allergic reactions to skin products.

It assesses the effectiveness of barrier creams.

It ensures the integrity of epidermal surfaces.

It measures loss of stratum corneum integrity. (correct)

What is the maximum exposure time for chemicals during the TER testing method?

24 hours Signup and view all the answers

In the Draize skin corrosion test, the skin is tested on which animal model?

Rabbit Signup and view all the answers

Which of the following regulatory frameworks requires data on skin corrosion effects?

EU REACH Regulation Signup and view all the answers

Which subcategory under the corrosive classification system indicates a 'moderate corrosive'?

1B Signup and view all the answers

What mechanism is utilized for measuring skin impedance in the TER test?

Low-voltage alternating current Wheatstone bridge Signup and view all the answers

What is the maximum allowable mercury content in cosmetics according to the FDA?

1 ppm (1000 μg/kg) Signup and view all the answers

Which of the following countries was found to manufacture the highest percentage of mercury skin lighteners sampled in recent studies?

Pakistan Signup and view all the answers

In the original Draize test, what quantity and form of substance is introduced into the rabbit's eye?

0.1 mL of a liquid or 100 mg of a solid Signup and view all the answers

How long are the subjects monitored after the Draize test for signs of pain and distress?

1 hour to 21 days Signup and view all the answers

Which online platforms were identified as sources for illegal mercury skin lighteners entering the EU?

ebay and aliexpress Signup and view all the answers

What is the structure of the Draize test modified version regarding the quantity of test substance introduced into the eye?

Instillation of 10 µL of a test liquid or 10 mg of a test solid Signup and view all the answers

Which of the following is NOT a common effect of mercury toxicity on vision?

Increased night vision Signup and view all the answers

During evaluations of ocular irritancy, how is the control eye treated?

It is not treated at all. Signup and view all the answers

What is the primary function of the visual cortex located in the occipital lobe?

Interpreting and processing visual information Signup and view all the answers

Which area of the visual cortex is primarily responsible for receiving input signals from the retina?

V1 Signup and view all the answers

How does lead exposure affect the visual cortex in adults?

Produces structural and functional deficits Signup and view all the answers

What is a characteristic symptom experienced by individuals poisoned with methyl mercury?

Progressive constriction of the visual field Signup and view all the answers

According to cosmetic regulations, what is the status of mercury and its compounds in cosmetic products?

Banned as ingredients Signup and view all the answers

Which area of the visual cortex is primarily affected by lead exposure related to peripheral vision?

V1 Signup and view all the answers

In the context of visual function, what symptom may indicate damage due to methyl mercury toxicity?

Visual field loss Signup and view all the answers

What percentage of formic acid is typically found in styling mousse?

6.94% Signup and view all the answers

Study Notes

Cosmetic Product Preservation

Formic acid is an antimicrobial agent used in cosmetics, with concentrations found in various products:
- Styling mousse (6.94%)
- Shampoo for colored/highlighted hair (2.89%)
- Personal hygiene products (2.33%)
- Classic shampoo (1.92%)
- Liquid soap (1.81%)

Visual Cortex and Neurotoxicity

The visual cortex is located in the occipital lobe and processes visual information. It features six areas: V1, V2, V3, V4, V5, and the inferotemporal cortex.
V1, the primary visual cortex (Brodmann area 17), is crucial for receiving signals from the retina.
Lead exposure leads to structural and functional deficits in the visual cortex, particularly affecting peripheral vision.
Methyl mercury exposure causes progressive visual field constriction, poor night vision, and severe damage to peripheral visual cortex regions.

Mercury in Cosmetics Regulation

Under Regulation (EC) N° 1223/2009, mercury and its compounds are banned as cosmetic ingredients in the EU, except for specific benign uses in eye makeup at controlled concentrations.
The FDA permits a maximum mercury content in cosmetics of 1 ppm (1000 μg/kg).
Investigations by the Zero Mercury Working Group (ZMWG) reveal continued illegal importation of high-mercury skin lighteners within the EU.
Most illegal products sampled originated from Pakistan (43%), Thailand (8%), China (6%), and Taiwan (4%).
Sampling from Belgium (2020-2022) showed 16 of 23 tested products contained mercury, with levels from 1000 to 18,821 ppm.

Draize Test for Ocular Irritancy

The Draize test evaluates ocular irritancy in albino rabbits by administering a test substance into one eye while the other serves as a control.
Modified Draize test methods involve a smaller volume of test liquid and saline rinse, assessing reactions over longer durations (1 hour to 21 days).

Skin Corrosion Regulations

Skin corrosion assessments are mandated by several regulations including CLP Regulation (1272/2008) and REACH (1907/2006).
Corrosive substances are categorized by observable skin effects in live rabbits using the Draize test.
EU has subcategories for corrosive substances classified by exposure time: Category 1A (strong), 1B (moderate), 1C (mild).
Accepted testing methods for skin corrosion include:
- In vivo Draize rabbit test (OECD, TG 404)
- In vitro Transcutaneous Electrical Resistance (TER) test (OECD, TG 430)
- Reconstructed human skin models (EpiSkin, EpiDerm, etc.) (OECD, TG 431)
- Corrositex (OECD, TG 435)

Transcutaneous Electrical Resistance Test Method (TER)

The TER evaluates the integrity of the skin barrier, as corrosive materials can impair the stratum corneum.
The test applies a chemical to rat skin discs for up to 24 hours to measure skin impedance using a Wheatstone bridge, revealing skin integrity loss at reduced resistance levels.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz explores the role of antimicrobial agents in cosmetics, specifically focusing on formic acid concentrations in various products. Additionally, it delves into the structure and importance of the visual cortex, the effects of neurotoxic substances like lead and methyl mercury on vision, and regulatory aspects concerning mercury in cosmetics. Test your knowledge on these crucial health topics!