Sunscreens additives

A series of nine sunscreen additives (Uvinuls) were separated and quantitated on a C g column (A = 292nm) using a two-iamp 2/3/95-> 35/35/30 (at 50 min) 100/0/0 (at 60 min) methanol/acetonitrile/water (1% w/w acetic acid) gradient [257]. The compounds resolved included 2-hydroxy-4-methoxy-, 2,2 -dihydroxy-4,4 -dimethoxy-, 2,4-dihydroxy-, and 2,2, 4,4 -tetrahydroxybenzophe-... 

Alkoxyhydroxybenzophenonesulfonic acids are used in the manufacture of cosmetic sunscreen additives they are synthesized by sulfonation of the parent alkoxyhydroxybenzophenones with chlorosulfonic acid at temperatures in the range (—20 to 100 °C) using an aliphatic or aromatic ester solvent. " For instance, 2-hydroxy-4-methoxybenzophenone reacts with chlorosulfonic acid (2.6 equivalents) in ethyl acetate at 0-5 °C (30 minutes), then at room temperature (12 hours) to yield 4-hydroxy-2-methoxybenzophenonesulfonic acid (80%). " The sulfonation may also be effected in excellent yield (95.3%), by reacting the substrate with an equimolar amount of chlorosulfonic acid in dimethyl carbonate at 10-35 °C (1 hour). " In this example, of course, the sulfonation is greatly... 

Toxicology Completely nonirritating to skin minimal/mild eye irritant Uses Surfactant, foam booster/stabilizer, wetting agent, detergent for personal care prods. solubilizer for fragrances, preservatives and sunscreen additives... 

All fluoroquinolone drugs can cause pain, inflammation, or rupture of a tendon. The Achilles tendon is particularly vulnerable. This problem can be so severe tiiat prolonged disability results, and, at times, surgical intervention may be necessary to correct die problem, hi addition, the fluoroquinolone drugs, particularly sparfloxacin and lomefloxacin, cause dangerous photosensitivity reactions. Fhtients have experienced severe reactions even when sunscreens or sunblocks were used. 

The concentration levels observed in sewage sludge show that UV filters originate mainly from private households, but besides this, surface runoff and industrial discharges may be considered as additional sources. This indicates that in addition to sunscreens, cosmetics and other personal products, UV filters from plastics, textiles, and other materials can be released to the environment by either volatilization or leaching. 

The list of new chemicals whose presence in the environment represents an ascertained or potential risk is sizeable and broadly contains resins, plastics, and plastic additives (e.g., plasticizers and flame retardants) pharmaceuticals and personal care products (e.g., disinfectants, fragrances, sunscreens, antibiotics, drugs of abuse, and natural and synthetic hormones) detergents and other cleaning... 

As mentioned in Sect. 13.3.6, carotenoids serve mainly as accessory pigments in the light harvesting complexes of the photosynthetic apparatus, and additionally as cellular protection against ROS. Whether carotenoids also act as passive UV-sunscreens is... 

Chlorinated swimming pool exposures have also been Unked with respiratory effects, including asthma [140, 150-152]. Trichloramine, which is formed by the reaction of chlorine with urea (from sweat and urine), has been suspected in these cases of asthma. In addition to sweat and urine, pool waters also contain other DBF precursors, such as skin cells, hair, and lotions/sunscreens. 

Figure 9 shows the spectra obtained from the application of the action spectrum for the global, diffuse and direct irradiances for the same case. It can be seen the change in the spectra and the increase of the importance of diffuse irradiance relative to global. In this context, it can be expected that UV diffuse radiation have an important role in the erithema formation. This result supports the idea that shadow is not enough to avoid a sunburn and that additional protection measures must be taken in order to avoid also the exposition to diffuse radiation (sunscreens, clothes, etc). 

The kinetics of the addition of IV-acetyl-L-cysteine, N-acetylcysteamine, and N2-acetyl-L-lysine (NAL) to / -methoxycinnamate, / -methoxycinnamide, anthranilate, and crotonyl or sorboyl thiol ester have been studied, and the thiol addition products identified. The reaction rates increased at higher pH and the crotyl thiol ester was found to be 7.9 times more reactive than a sorboyl thiol ester toward IV-acetyl-L-cysteine addition. These unsaturated thiol esters may serve as a means of covalently binding UVA and UVB sunscreens to the outer layer of skin to provide long-lasting protection.128... 

Other compounds such as phlorotannins, sporopollenin, coumarins, tridentatols, polyphenolics, and several as yet unidentified substances (e.g., P380) have also been implicated as UV protectants that can increase UV tolerance.57-63 With the rapidly accelerating rate of research in the area of aquatic UV photobiology, it is highly likely that additional new types of UV-screening compounds will continue to be discovered. Many of these secondary metabolites probably have multiple protective functions. For example, tridentatols serve as allelopathic agents, antioxidants, and sunscreens.57,58,64... 

The full range of MAA functions is not yet known. These compounds may be involved in a variety of metabolic processes in addition to their most commonly assumed role as sunscreens. It is possible that UV absorption may prove to be an ancillary and not primary function of these compounds, at least in some organisms. 

Uses Thiram is a dimethyl dithiocarbamate compound and appears as a white to yellow crystalline powder with a characteristic odor. Thiram is used to prevent crop damage in the field and to protect harvested crops from deterioration in storage or transport. Thiram also is used as a seed protectant and to protect fruits, vegetables, ornamentals, and turf crops from a variety of fungal diseases. In addition, it is used as an animal repellent to protect fruit trees and ornamentals from damage by rabbits, rodents, and deer. Thiram is available as dust, flowable, wettable powder, water-dispersible granules, water suspension formulations, and in mixtures with other fungicides. Thiram has been used in the treatment of human scabies, as a sunscreen, and as a bactericide applied directly to the skin or incorporated into soap.17,50,52... 

Discoloration is also sometimes observed in alcoholic perfumes in clear glass bottles. Here the problem involves the action of light and air upon sensitive perfume materials. It can sometimes be alleviated by the addition of a sunscreen to the finished perfume. Sunscreens should not be incorporated directly in perfume oils since they may contribute to instability. 

Therefore inorganic sunscreens commonly used in cosmetic industry should be carefully tested for their photoactivity and phototoxicity. Sunscreens based on titanium and zinc oxides should contain additional antioxidants, eg a-tocopherol or j5-carotene. Even more efficient protection against unwanted ROSs can be achieved by a smart titanium dioxide modification that would block its photocatalytic activity. Recently Lee et al. described a hydrophobic multicomponent polymer coating for nanocrystalline Ti02 containing natural antioxidants extracted from grape seeds... 

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