Duty of care breach and damages
Duty of care is the foundation of negligence, it means defendant have a legal duty to take care of the people legally around him. We can judge whether defendant has duty of care about plaintiff with three factors. First, foreseeability, the defendant must foresee that the plaintiff is likely to be affected by his act or omission. Second, proximity, the defendant may be able to foresee numerous consequences arising from his act or omission, but he cannot always be liable. Proximity test narrows the scale of foreseeability. It requires there should be closely link between defendant and plaintiff both in time and space. Finally, fairness, justice and reasonableness, it means the duty should be fair to both parties to insure the equity of law.
Breach of duty is a series of standards determining whether defendant breaches duty of care.
Causation is the causal relationship between defendant’s conduct and result, which means the breach of duty should substantially contribute to the damage occurred. The causation should be both in fact and in law.
After reading the whole case, I think, there are 4 events may cause tort claim. Three are about product liability. The other one is relevant to psychiatric illness. So, there are two legal issues here.
First issue, does the manufacturer hold the product liability?
When tort claim is relevant to product liability, normally, the plaintiff is ultimate consumer, and the manufacturer is defendant. Manufacturer is definite as someone who manufactures something. In tort law manufacturer could be distributors, retailers, suppliers, and so on. Product has been interpreted expansively to every type of product that is manufactured, and is capable of causing injury or damage.  Ultimate consumer can be definite as Individual (such as a housewife) or a group (such as a family) which actually consumes or uses a good or service. 
Talk about eye shadow first. Here, product is “Perfect Eye". Manufacturer is ‘Marnier’. Although the product is bought from ‘Bride Perfect’ in the ‘Bridal Shopping Centre’, both the shop and shopping center are sellers. They don’t have any impact on the products. They just supply a way for the manufacturer to sell its products. Ultimate consumer is Beauty, the bride. Despite that Candy go to the shopping center and buy the eye shadow, Beauty actually use this cosmetic and the allergic reaction occurred on her face. Furthermore, under the neighbor principle established by Donoghue v Stevenson  , both parties and non-parties to the contract can sue the manufacturer for defective products causing loss or injury. So, Beauty is the person who really used the goods and got injury. She should be recognized as ultimate consumer.
In this case, according to the warning printed on the package, the manufacturer must know his product may cause allergic reaction to some consumers. Here，the proximity exists obviously. Beauty used the eye shadow, and then she began to experience itchiness on her eyelids. The doctor was certained that the allergic reaction was caused by the components of ‘Perfect Eye’. There is close link between the product and damage. To insure the product is suitable and safety to consumers, that’s the basic requirement of manufacturer, which is accordance with fairness, justice and reasonableness.
Clearly, the manufacturer has the duty of care. But does the manufacturer do something breach the duty of care? In my point of view, as a manufacturer of cosmetics, the defendant should have knowledge about suitable warning. As the warning written on the package of the eye shadow, the defendant may say that he has warn the consumers to exam the product on the back hand before formally use it. Can this warning disclaim the liability of manufacturer? It depends. The manufacturer must have a knowledge about which size of warning can be noticed by a reasonable person. In the case, it says that the warning was printed in very small size. If the whole package is not big, the warning has to be printed in very small size, a normal person can notice this warning but Beauty ignored it, the liability will be transferred to Beauty. In Jones v Livox Quarries Ltd,  defendant is not liable because the plaintiff ignored defendant’s order and the risk is created by his own negligence, which called Contributory Negligence. Similar here, the manufacturer has already performed his duty, but Beauty ignored it and the injury is caused by her own negligence. The defendant is not liable. But if the manufacturer printed the warning in very small size on purpose and normally almost consumer won’t see it, there will be a warning defect and the manufacturer breach duty of care. Because he didn’t willing to tell consumers the product may cause allergic reaction but he printed a very small warning to avoid the liability. When this condition fulfilled, the manufacturer should be liable for Beauty’s injury.
Another question, will the retailer prevent the manufacturer from liability? Maybe the defendant will say the product is selling by the ‘Bride Perfect’ or the ‘Bride Shopping Centre’. I think, it can’t establish. The products reach consumers in the form which it left the manufacturer. There is no reason to contemplate an examination by the retailer.
Obviously, what Beauty suffered will not occur but for the manufacturer’s breach of duty. It’s not beyond the reasonable limits of defendant’s liability and it can be foresaw.
To conclude, if the ‘Marnier’ printed the warning in very small size on purpose, Beauty can sue it. On the contrary, she cannot claim a tort.
Next, analyze the ‘Plump Up’. The product is moisturising cream. Similar as the ‘Perfect Eye’, the manufacturer is ‘Marnier’, and the ultimate consumer is Beauty. The manufacturer should have duty of care to Beauty.
According to the doctor’s report, it’s hard to know Beauty’s shin rash caused by ‘Plump Up’ or ‘Plump Up’ combined with ‘Rosy Glow’. So, an issue occurred, whether the cream is a product with warning defect? In Lam Mo Bun v Hong Kong Aerosol Co Ltd& Ors  , the defendant was liable because he didn’t warn the consumers that the insecticide would cause an explosion under certain circumstances. From that case, we know that the manufacturer has the duty to warn consumers about foreseeable dangerous of the product. In our case, we can sure that shin rash doesn’t cause by the ‘Rosy Glow’ because Beauty had used it for 2 years. So, it should be caused with the ‘Plump Up’. The manufacturer should print a warning on his product telling consumers the risk of using the product and warning them don’t use it with other products or test it first. As a manufacturer of cosmetics, the manufacturer should know that chemical composition will raise allergic reaction. The defendant breaches his duty of warning. He should be liable for the damage of plaintiff.
It’s a multiple cause here. Although which certainly cause the allergic reaction. Obviously, ‘Plump Up’ is the main cause.
Summary, Beauty can sue the ‘Marnier’ for breaching the duty of warning.
Third, let’s talk about the drink used on the wedding banquet. Product is ‘Mango Cola’. The manufacturer is ‘Best Food’ catering company which supplied the food for the wedding banquet. Ultimate consumers are people who have drunk the drink and finally got sick with diarrhoea. As the analyzing of the eye shadow, similar here, the manufacturer has duty of care of consumers. In Great v Australian Knitting Mills,  the manufacturer, defendant is liable because its defect product. Similar here, the ‘Mango Cola’ is not safety for drinking, and finally it made the people who drunk it injury. So, the manufacturer doesn’t perform the duty of care. As a manufacturer of food, the defendant should have the knowledge about the standard of health and safety food.
To sum up, the consumers who drink the ‘Mango Cola’, finally got sick and rush to the hospital can claim a tort against the manufacturer because of its defective products.
Second issue, can Teena sue the catering company based on psychiatric illness?
As the neighbor principle, the manufacturer should have duty of care on the people who consume the product or closely link with it. The duty of care contains both on physical injury and psychiatric illness. If the manufacturer can foresee the physical injury caused by its defective products, it is sufficient to bring it a duty regarding with psychiatric illness. Plaintiff who suffered psychiatric illness caused by defendant’s negligence can sue if he fulfilled two conditions: 1) plaintiff’s injury accepted as psychiatric illness. 2) plaintiff is a primary or secondary victim. Primary victim is person who is under potential danger. Secondary victim is person who is not in danger but witness it and worry about it.
In this case, Teena suffered phobia for drinking liquid, which is one kind of mental impairment. So, there is no doubt it can be accepted as psychiatric illness.
Is Teena a primary victim, secondary victim, or neither? It depends. It can be divided into three situations. First one, she can be recognized as a primary victim. If Teena has drunk some of the ‘Mango Cola’, although she never got sick with diarrhoea, she is already under the danger. She may worry about herself. In Dulieu v White & Sons,  the plaintiff is recovered because the injury was arose from a reasonable fear of immediate personal injury to herself. Here, Teena has drunk the drink, others who have drunk it got sick and rash to the hospital. May be next minute, she will be sick like others, so it is reasonable for her to worry about herself. Her psychiatric illness should be recovered. Second situation, she can be recognized as a secondary victim. In this situation, Teena didn’t drink the cola, but someone who has closely relationship with her has drunk it. To determine whether someone is a secondary victim, he should be the place when accident happened, he should saw it, and he should have relationship with primary victim. Teena was at banquet and saw her relative drunk cola and got sick, may be her son or father and so on. She may be worry about them and then nervous shock. Just like the Hambrook v Stokes Bros  case, mother was recovered because of worrying about her daughter’s safety. Third situation, Teena is neither a primary victim nor a secondary victim. In this situation, she didn’t drink any ‘Mango Cola’. There are no people who have closely relationship with her have drunk the cola and got sick. She cannot claim for anything.
To conclude, if Teena has drunk the ‘Mango Cola’ or her relative has drunk it and got sick, she can sue the defendant for psychiatric illness. Otherwise, she cannot.
All in all, in this hypothetical case, Beauty can sue the ‘Marnier’ because of the shin rash caused by ‘Plump Up’. She can also sue the ‘Marnier’ based on allergic reaction if the warning is really small and normally consumers cannot find it. People who had drunk ‘Mango Cola’ and got sick can claim a tort to ‘Best Food’. Teena, if she drunk the cola, or people who has closely relationship with her drunk it, she can sue the ‘Best Food’ company because of the psychiatric illness.