Voice assistants made popular by Amazon and Google are seemingly everywhere in the home - from internet-connected refrigerators, to toilets and lightbulbs.

They bring with them the benefit of convenience as a growing number of users can now complete everyday tasks, like locking their door or turning on the light, with just their voice.

But the always-on nature of internet-connected devices has raised some concerns over just how much data these applications are collecting and what they're doing with it, according to Bloomberg.

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A woman is seen controlling her Philips Hue smart lightbulb with her voice assistant. Concerns have grown around how much data these applications are collecting and how it's being used

In the past, if users asked Alexa to turn on their smart bulb, Alexa would transmit code to the device to check if it was on or off, receive confirmation that it was off and then tell it to turn on, Bloomberg noted.

However, increasingly, Google and Amazon are requiring devicemakers to make it so that their appliances are continuously transmitting data around whether they're off or on.

It likely extends to many internet-connected devices around the home, like smart TVs, smart locks, smart thermostats and more.

The practice has thrown into question whether or not users are totally aware of this.

What's more concerning is that it raises the possibility of Google and Amazon using the data for the purpose of targeted marketing.

Experts fear Google and Amazon could be collecting mass amounts of users' smart appliance data for targeted advertising purposes. As an example, if Amazon becomes aware of when your child goes to bed by looking at the time their smart light bulb is turned off, it could use that data to push related products to the user, such as an app for nursery rhymes

As an example, if Amazon becomes aware of when your child goes to bed by looking at the time their smart lightbulb is turned off, it could use that data to push related products to the user, such as an app for nursery rhymes.

HOW CAN YOU FIND OUT WHAT GOOGLE ASSISTANT IS RECORDING? What does Google's Voice Assistant record? Google's Voice Assistant could be recording everything you say. As part of this process, Google keeps copies of clips made each time you activate it, but it has emerged that background chatter could be enough to trigger recording. MailOnline has received a number of transcripts of conversations that show how Voice Assistant may be recording your conversations without you knowing. One example from an anonymous user appears to have registered the code to their back door entry system, while chatting with a friend. A written transcript of the conversation said: 'If you ever get booked down to my house for some reason the key safe for the back door is 0783.' How can I see what it has recorded? Your audio is saved to your account only when you're signed in and Voice & Audio Activity is turned on. Audio can be saved even when your device is offline. To see your saved audio, sign in with your Google account information. To delete info, click on the three dots in the top right corner and choose 'Delete activity by'. This will take you to a window where you can pick if you would like to delete any information. What does Google say about it? A spokesman for the firm said: 'We only process voice searches after the phone believes the hot word 'OK Google' is detected. 'Audio snippets are used by Google to improve the quality of speech recognition across Search.' They added that ambient recording is never transmitted to the cloud. Google's support site says that the firm records your voice and other audio, plus a few seconds before, when you use audio activation. This includes saying commands like 'OK Google' or tapping the microphone icon. Advertisement

'You can learn the behaviors of a household based on their patterns,' Brad Russell, a researcher for Parks Associates Inc., told Bloomberg.

'One of the most foundational things is occupancy. There's a lot they could do with that.'

Additionally, Amazon and Google have each faced issues with user data privacy.

In December, an Alexa user mistakenly accessed about 1,700 voice recordings from a stranger's device as a result of 'human error.'

When Google first debuted Assistant in 2016, it raised fears of just how much data the company would need to be collecting on its users.

Amazon and Google don't appear to have any limits on what they can do with the information gleaned about users from their devices, according to Bloomberg.

Tech giants often justify this data collection by saying it improves the user experience, allowing the device to learn their preferences and make helpful suggestions accordingly.

Still, some dispute whether or not it's necessary to collect mountains of data from users.

'Oversharing for the sake of oversharing is probably never a good thing,' Ian Crowe, a senior director from Logitech International, told Bloomberg.

'We should have a good reason, and our users should agree it's a good reason.'

Some devicemakers have tried to establish greater controls around what kinds of user data is submitted to Amazon and Google, but so far, these requests seem to have fallen on deaf ears.

Amazon told Bloomberg that data used in status updates isn't sold for advertising, but the firm didn't specify how long it's stored for.

Google declined to comment to Bloomberg on how the data is used.

In the meantime, neither firm gives users many controls around what data is being collected or ways to stop it from being collected, short of unplugging the devices entirely.

'There isn't an implicit permission of, "Go ahead and take all my data whenever [something] changes,"' Martin Plaehn, CEO of smart-home system firm Control4, told Bloomberg.

'And we think if the world really knew that was going on, it would create a real kerfuffle.'

