Moisturiser. Also helps repair skin damage.
Single-celled micro organisms with ridged cell walls that multiply by dividing into two. Some bacteria cause illness and others cause spoilage.
Inhibition of bacterial growth.
Ingredients which provide positive benefits to the skin. E.g. skin needs to be well hydrated; ingredients (e.g. oils) are used that will provide a softening or soothing effect to the skin and they smooth dry and scaly skin.
Testing equipment for measuring skin hydration.
This can be claimed when a product has been proved to have good compatibility with the skin. A Primary Irritation test performed.
In Deb’s case, we used a 48 Hour Human Patch Test. 25 subjects are tested on the upper arm.
The test products are applied to the skin and covered with an occlusive patch which is left in place for 23 hrs. The subjects irritation scores (i.e. any skin reaction) are visually assessed 1 hour after removal of the patch. A second patch is the applied (assuming no skin reaction) for a further 23 hrs and a final assessment is made 1 hour after removal of the patch
Dibasic esters are highly effective solvents used for removing inks, resins and paints.
An excellent ‘dry feel’ emollient which also helps to prevent hand creams from feeling too greasy.
Food Poisoning Bacteria
These produce toxins, either in the food or in the body after consumption of contaminated food.
Certain cosmetic ingredients are not compatible with materials used for disposable gloves, particularly latex.
They can cause the glove to develop pin-holes or even to split. This can be particularly hazardous when the gloves are being worn for surgical use as bacteria from the surgeon’s hand can be transferred to the patient through the pin-hole.
Pieces of gloves are tested by applying hand cream to them and then storing the pieces at 40°C for 24 hours in order to “age” them.
BSEN tests (‘freedom from holes’, various tensile properties) are then performed on the pieces.
Gram –ve And Gram +ve
A staining method to differentiate bacteria.
Gram positive bacteria stain blue/violet and Gram negative bacteria stain pink. This is due to differences in the structure of the cell walls.
This structure difference is partly the reason why germicides can have different activities against G –ve and G +bacteria.
Ready-to-eat foods, which, under favourable conditions, support the multiplication of pathogenic bacteria and are intended for consumption without treatment, which would destroy such organisms.
Substances that absorb and promote the retention of moisture from the air.
By doing this they increase the water holding capacity of the stratum corneum (the top layer of the skin). Glycerin is a good example of this type of product.
Literally means “in glass”. A test that is done in the test tube or bottle rather than in a living organism.
In Vitro Filter Paper Test
This method involves the use of filter paper for determining the Moisture Penetration Rate through a thin film of a given skin protectant product.
A uniform thin film of test product is applied to a filter paper wick which is inserted into a circular filter paper. One end of the wick is placed in the test solution (e.g. water). Using an ink marker, the progress of the water front can be measured. The future the water front moves, the less effective the test product is.
Literally means “in the body of a living organism”. Refers to work done using human (or animal) subjects.
Moisturises and increases skin hydration which gives it excellent properties to keep the skin soft.
This natural fine white clay has excellent absorption abilities that gently draws out and absorbs excess oils and impurities from the skin.
Counts of microbes are quantitative – they provide a measure of how effective the germicide is against the test organism.
The results gained are usually quoted as log or percentage reduction. The log reduction is calculated by converting the microbe counts (e.g. number of bacteria) to log 10 taking the test sample result away from the control (i.e. sample without germicide).
The log reduction can be related to percentage reduction:-
Log 1 decrease is equal to 90% Log 2 decrease is equal to 99% Log 3 decrease is equal to 99.9% Log 4 decrease is equal to 99.99% Log 5 decrease is equal to 99.999%
These percentages are critical as the skin may contain millions of bacteria – the food industry normally sets acceptable limits at the low 100’s.
For example, if there are 6,000,000 bacteria, a 90% decrease will still leave 600,000 bacteria on the skin or surface. A 99.999% decrease will only leave 60 bacteria.
Ambient stable foods that do not normally support the multiplication of pathogens. However, they may occasionally be responsible for food borne illness if they are ready-to-eat foods contaminated with low-dose pathogens, for example, lettuce.
Add moisture to the skin.
For example, Urea is employed as a hydrating agent. It has a high moisturising factor and decreases skin roughness. It also has some anti-inflammatory properties. Allantoin also acts as a skin healing and softening agent i.e. it soothes and smoothes the skin.
Microsopic plants (fungi) that may appear as woolly patches on food.
Moisture Penetration Rate Test.
In vitro method for evaluating skin protectant formulations for barrier properties. The method involves the use of paper chromatography for determining the Moisture Penetration Rate through a thin barrier of a given skin protectant product.
A substance that will not transfer odour or taste to a food stuff.
An occlusive film on the skin prevents the evaporation of water from the stratum corneum, or top layer, of the skin.
Para-amino benzoic acid (PABA) is an effective sunscreen agent but it can cause skin sensitivity in some people causing an itchy rash.
It can also darken to stain clothing yellow.
Moisturising agent. Decreases skin roughness. Acts as an aid in wound healing helping in tissue repair.
Paraffinum Liquidum is a very effective emollient and lubricant. It also helps to protect the skin by forming a barrier to moisture.
An organism that can cause disease (e.g. Salmonella).
PEG-7 Glyceryl Cocoate
Emollient and re-fatting agent.
Emollient and lubricant. Helps protect skin by forming a barrier to moisture.
Polyquaternium-7 is a highly efficient skin conditioning polymer.
Resident Organisms / Flora
These are the indigenous skin flora which multiply and persist on the skin. They are mainly non-pathogenic organisms, though occasionally S. aureus and, in damaged or persistently immersed skin, (e.g. under wedding rings) some Gram negatives, may become residents.
Repeat Irritation Test
This is used to assess the efficacy of barrier creams against irritants on human skin. The test product (barrier cream) is applied and left to dry for 30 minutes. A plastic chamber is fixed over the site and an irritant liquid is added , left in contact for 30 minutes, then the chamber and liquid are removed and the skin dried. This is repeated daily for 9 days. Assessments of the skin are made every day both visually and by using instruments (e.g. Corneometer, tewameter). All results are collated and analysed to determine if the test product provides an effective barrier to the test irritant.
This has very good water repellence and is spread easily on the skin.
Skin Barrier Function
The skin has many properties and one of them is to provide a protective barrier to the body. If this barrier is damaged by cuts or burns, then not only is there discomfort, but also the possibility of infection caused by micro organisms entering through the damaged skin. Likewise, environmental substances such as chemicals can gain access.
In order to optimise the barrier function of the skin, the skin must be kept in good condition and be well moisturised.
The stratum corneum is the top layer of the skin. The water content (hydration) of the stratum corneum is important for skin condition since it acts as a plasticizer. Water content may be measured using the electrical properties of the skin (capacitance) using to Corneometer.
Sun Protector Factor
This number, usually between 0-50, determines the amount of sun that is blocked by a sunscreen. A number 15 sunscreen blocks 95% of the suns rays. Dermatologists usually recommend applying a higher SPF(30) as it has been shown that people usually apply less sunscreen than is needed.
This is performed on human volunteers using a Xenon Arc Solar Simulator. A test site on the back is exposed to a series of timed incremental UV exposures at 25% increments. The individual subject’s MED (Minimal Erythema Dose) is the shortest time of exposure that produces minimally perceptible erythema at 20 to 24 hours post irradiation. (Erythema is a reddening of the skin.) The SPF is calculated from the MED of unprotected skin. (No sunscreen.) Waterproof determination is again performed on human volunteers. Basically the test is as above, but before exposure to the solar simulator, the test area is immersed in water at 75-80°F in a whirlpool tub. There are 4 x 20 minutes of moderate activity in the water, each followed by 20 minutes of rest period out of the water. The SPF is calculated as above.
Contamination of food from undesirable flavour or odours, for example, butter absorbs paint fumes, and chocolate stored next to detergent washing powders will taste soapy.
Water is continually evaporating from the skin surface and being replaced from below. Transperidermal waterloss (TEWL) is the rate of water loss from the skin surface. TEWL increases in damaged skin (e.g. dry skin) and may increase before the damage is apparent.
TEWL may be measured with the Tewameter.
Testing equipment for measuring transepidermal waterloss (TEWL).
Transient Organisms/ Flora
These are micro organisms which are deposited, but do not multiply on the skin. They are readily transferred from the skin to the next thing touched. They are equally readily removed by cleansing methods.
These rays penetrate into the connective tissue and are the primary cause of chronic light-induced damage such as premature skin ageing.
These rays penetrate into the deepest cell layers of the epidermis and are the main cause of sunburn, DNA damage and development of skin cancer.
These rays from the sun are absorbed by the upper atmosphere (ozone layer) and do not reach the earth’s surface. These rays are the most harmful to plant and animal life, so if the ozone layer thins, we may be exposed to UV-C rays in the future, causing more skin cancer and eye damage. However, UV-C rays can be produced on earth by arc welding and these can give rise to eye damage.
Wheatgerm is an oil very high in essential fatty acids, vitamins A and D and is one of the richest sources of vitamin E.
Wheatgerm is highly skin compatible and aids in renewing skin cells.
Xanthum Gum is a naturally derived thickener, stabiliser and skin soother.
An unicellular fungus which reproduces by budding and grows rapidly on certain foodstuffs, especially those containing sugar. Yeasts are chief agents of fermentation (sugar converted to alcohol and carbon dioxide).