A composition for protecting human skin from harmful effects of the sun, the composition comprising a topically effective amount of:

• (a) a first chemical compound that absorbs ultraviolet light sufficiently to reduce significantly the damage to human skin from harmful effects of ultraviolet light; and
• (b) a second chemical compound having the formula:

  wherein:

• Q represents 4-E-2-R₃-1-quinolinium;
• E represents NR₁R₂, COO R₁, OR₁, I, Br, Cl, F, or NO₃
• N represents a nitrogen atom;
• R₁ and R₂ independently represent hydrogen or lower alkyl;
• R₃ represents E, hydrogen or lower alkyl;
• T represents hydrogen or a chain comprising m atoms, the atoms in the chain being t carbon atoms and 0 to approximately 0.5t heteroatoms;
• the minimum value of m is 6;
• the maximum value of m is 22;
• X represents an anion; and
• u and v represent 1, 2, or 3 with the proviso that u=v.