```md
<!-- MyComponent.stories.mdx -->

import { Meta, Story, Canvas } from '@storybook/addon-docs';

import MyComponent from './MyComponent';

<Meta title="A MDX story using environment variables inside a .env file" />

export const Template = (args) => <MyOtherComponent {...args} />

<Canvas>
  <Story
    name="A MDX story using environment variables inside a .env file"
    args={{
      propertyA: process.env.STORYBOOK_DATA_KEY,
    }}>
    {Template.bind({})}
  </Story>
</Canvas>
```