United States

Regulatory information applicable to aloe vera products marketed in the United States is summarized below.

Foods, Beverages, and Dietary supplements
Use of aloe vera as an ingredient in consumer products such as foods, beverages and dietary supplements is under the oversight of the U.S. Food and Drug Administration (FDA) under the Food, Drug, and Cosmetic Act (FDCA). These regulations include requirements for facility registration; use of good manufacturing practices; labelling, including for the presence of major food allergens; and safety requirements, including, as applicable, new dietary ingredient (NDI) and food additive regulations (e.g., establishment of ingredients as GRAS, or generally recognized as safe).
Regulatory information for marketers of conventional food and beverage products can be found here:  https://www.fda.gov/Food/GuidanceRegulation/default.htm
Similar information for marketers of dietary supplements can be found here: https://www.fda.gov/Food/GuidanceRegulation/GuidanceDocumentsRegulatoryInformation/DietarySupplements/default.htm
Acidified and Low acid Canned Foods
Some aloe vera food products may need to comply with the FDA’s regulations for acidified or low acid canned foods. These regulations require commercial processors of shelf stable acidified foods and low-acid canned foods in a hermetically sealed container to register each establishment and file scheduled processes with the FDA for each product, product style, container size and type and processing method.
More information about this regulation can be found at this link:
Use of aloe vera ingredients in cosmetics and personal care products is also under the regulatory oversight of the FDA. Marketers of cosmetics and personal care products that contain aloe vera ingredients must comply with the applicable requirements of the FDCA and governing regulations for cosmetic and other personal care products. Such regulations include requirements for packaging and labeling, specifications for ingredients such as color additives, and draft guidance on cosmetic GMPs. FDA also offers voluntary facility registration and cosmetic ingredient statement programs.
Information about these regulations and guidance for achieving compliance can be found on the FDA website at:
California Proposition 65
Proposition 65 (“Prop 65”), or “The Safe Drinking Water and Toxic Enforcement Act of 1986,” is a California right-to-know law that was passed by voters in 1986. Among other things, the law creates a requirement for companies to inform the public about the presence of certain substances in the products they sell or use. These “Prop 65-listed chemicals” are ones for which the State of California has decided that information about the chemical’s toxicity satisfies the regulatory requirements for addition to the Prop 65 list of chemicals. 
When such a substance occurs or may occur in a product above a very low level, the company is required to provide “clear and reasonable” warnings to the public that the product contains or exposes the consumer to “chemicals known to the State of California to cause cancer” or “chemicals known to the State of California to cause birth defects or other reproductive harm.” Depending on the circumstances, companies may provide the warning by printing it on product labels, including it in documents that accompany the product when it is shipped to a consumer in California, or posting it on signs in California businesses. 
Prop 65 warnings are required for chemicals that are commonly present in a wide variety of everyday products such as foods, dietary supplements, and beauty care products, and as well as for substances such as cleaners, pesticides, gasoline, car exhaust, and cigarette smoke. As a result, warnings can be seen not only on product labels but also posted throughout California in establishments such as restaurants, coffee shops, hotels, stores, buildings, and parking garages.  
On December 4, 2015, California announced that "Aloe vera, non-decolorized whole leaf extract" had been added to the Proposition 65 list.
Read the IASC Position Statement about the listing of "Aloe vera, non-decolorized whole leaf extract".
The IASC has developed a "Frequently Asked Questions" document about Proposition 65 and the listing of this aloe ingredient.
IASC Position Paper: NTP 2-Year Oral Consumption Study 
The National Toxicology Program (NTP) is an US federal interagency program whose objective is to evaluate substances of possible public health concern by developing and applying tools of modern toxicology and molecular biology. Aloe vera was nominated along with several other botanical substances for review by NTP in the late 1990s.
In 2013, the NTP released its final Technical Report titled "Toxicology and Carcinogenesis Studies of a Nondecolorized Whole Leaf Extract of Aloe barbadensis Miller (Aloe vera) in F344/N Rats and B6C3F1 Mice (Drinking Water Studies)." NTP concluded that the 2-year carcinogenicity study performed as part of the analysis demonstrated that the non-decolorized whole leaf extract used as the test substance was associated with the development of intestinal tumors in rats.   
The IASC position paper was developed in order to educate consumers, retailers, and industry on the potential issues  and questions that could arise following the publication of the NTP study results.